202110728-PERFORM-STUDENT-WORKBOOK-SCIENCE-G10-FY_Optimized

12. Electricity Learning Outcomes • List out the practical applications of system of resistors, heating effect of electric current and At the end of this lesson, students will be able to: power. • Draw a circuit diagram. • Explain the terms like resistance, current, • State the Joule’s law of heating. • Convert the unit for measuring power. potential difference, resistivity and power. • State the Ohm’s law. • Explain system of resistors. • Explain the heating effects of current. Concept Map Electricity Electric current System of Heating effect of Electric power and circuit resistors electric current Current Voltage Resistors in series Resistors in par- allel Resistance Key Points • Due to the conversion of some amount of elec- tric energy, passing through the conductor, into • Electric current is expressed by the amount of heat energy, this effect of electric current is charge flowing through a particular area in unit called heating effect of electric current. time. The unit of current is Ampere. • The heat produced in a resistor is directly pro- • The potential difference between two separate portional to the square of given resistance, re- points is defined as the work done to move a sistance of the given current and time for which unit positive charge from one point to another. the current flows through the resistor. It’s unit is volt. • Power is the rate of doing work. It’s unit is Watt. • Ohm’s law states that the potential difference Keywords – Current, charge, resistance, resistivi- across the ends of metallic wire in an electric ty, potential difference, ampere, volt, Ohm, Watt, circuit is directly proportional to the current Joule, Power, Fuse flowing through it. • Resistivity of a substance is equal to the resis- tance of a unit square of that substance. Its unit is Ωm. • Resistors can be connected in series or parallel combination. 87

12. Electricity Work Plan CONCEPT COVERAGE COVERAGE DETAILS PRACTICE SHEET SIMULATION/ PS-1 VIDEO Electric current and • Current PS-2 circuit • Charge Electric Current • Potential difference PS-3 Potential Difference • Circuit diagram • Ohm’s law PS- 4 Circuit Diagram • Factors on which Ohm's Law PS-5 resistance depend PS-6 Electrical Resistance Self-evaluation Factors Affecting System of resistors • Resistors in parallel Sheet Resistance • Resistors in series Resistors in Series • Practical applications of Resistors in Parallel resistors in parallel and series Heating effect of electric • Heating effect of electric current current • Joule’s law of heating • Practical applications of heating effect of electric current Electric power • Power • Units of power • Conversion of units of power Worksheet for \"Electricity\" Evaluation with self- check or Peer check* 88

PRACTICE SHEET - 1 (PS-1) I.  Fill in the blanks. 1. A continuous closed path of electric current is called a _____. 2. Electric current is the rate of flow of ____. 3. The SI unit of electric charge is ____. 4. 1 mA = ___ A. II.  Name the following. 1. An instrument used to measure the current. 2. An instrument used to measure the potential difference. 3. An instrument used to adjust the resistance. III.  Define these terms. 1. Ampere 2. Variable resistance IV.  Answer these questions. 1. Why are electrons not completely freely to move within a conductor? 2. State ohm’s law 3. State the factors on which the resistance of the conductor depends? PRACTICE SHEET - 2 (PS-2) I.  Solve these. 1. A current of 2 A is drawn by a wire for 60 seconds. Find the amount of electric charge that flows through the circuit. 2. An electric appliance does work of 250 J when charge of 7 C moves across the two points of the conductor. Calculate the voltage applied. 3. An electric appliance does work of 20 J when charge of 2 C moves across the two points of the conductor. Calculate the resistance across the conductor if a current of 0.75 A flows across it. 4. Calculate the number of electrons present in a charge of 3 Coulomb. 5. What will be the resistivity of a metal wire of 2 m length and 0.6 mm in diameter, if the resistance of the wire is 50 Ω. 89

PRACTICE SHEET - 3 (PS-3) III.  Calculate the total resistance in each of these circuits. I.  Multiple Choice Questions 1. 1. Is it preferable to connect bulbs in series or in 2. parallel? 3. a. Series b. Parallel c. Both series and parallel d. Neither series nor parallel 2. A device that opens and closes a circuit is a __________. a. Switch b. Electrical current c. Conductor d. Volt 3. A voltmeter should be connected to a circuit in __________. a. Parallel b. Series c. Series-parallel d. Short form 4. Resistors are connected end to end in ______. a. Series combination b. Parallel combination c. Circular combination d. Random combination 5. In series combination current passing through each resistor is ______. a. Different b. Same c. Zero d. High 6. Ammeter should always have a a. High resistance b. Low resistance c. Low voltage d. High voltage II.  Answer each of these questions - 7. Which are the two ways of connecting resistors? 8. Why is an ammeter likely to be burnt if you connect it in parallel? 9. State any two disadvantages of connecting devices in series. 90

PRACTICE SHEET - 4 (PS-4) I.  Answer each of these questions. 1. What is the heating effect of electric current? 2. State the Joule’s law of heating. 3. Name any four appliances whose working is based on the heating effect of electric current. 4. Why are the bulbs usually filled with inactive nitrogen? II.  Solve these. 1. Calculate the amount of heat produced when 6 Volts of potential difference is applied to a cir- cuit which produces a current of 10 A in 4 sec- onds. 2. An electric circuit produces heat of 243J in one second. The total resistance offered by the cir- cuit is 3 Ω. Find the current flowing through the circuit and potential difference applied. 3. An electric geyser draws current of 13 A from a 20V source to produce certain amount of heat in 10 seconds. An electric laundry iron draws a current of 5 A from a 35V source to produce cer- tain amount of heat in 20 seconds. Which appli- ance produces more heat? 91

PRACTICE SHEET - 5 (PS-5) I. Fill in the blanks. 1. _____ is the rate of doing work. 2. Power is the rate of consumption of _____. 3. The SI unit of power is ____. II.  Define the following - 1. Watt 2. Watt hour III.  Carry out the following conversions. 1. 1 kilowatt = ____ watt 2. 1 kW h = ____ J Solve these - 1. An electrical appliance is rated 1500 W, 250 V. This appliance is connected to mains of voltage 250 V. Calculate - (a) the current drawn, (b) the electrical energy consumed in 60 hours (c ) the cost of electrical energy consumed at rate of ₹ 4.50 per kWh. 2. Two bulbs A and B are rated 100 W, 120 V and 10 W, and 120 V respectively. They are connected across a 120 V source in series. (a) Calculate the current through each bulb. (b) Which bulb will consume more power?3. (c) Power consumed by the bulb 3. If an appliance consumes a power of 20 W when a potential difference of 40V, calculate the cur- rent flowing in the appliance. 92

PRACTICE SHEET - 6 (PS-6) I. Choose the correct option. 1. 1 volt is defined as a. Workdone/ time b. Work done / Charge c. Charge /time d. Volt / Ampere 2. In the above image what does A and V represent in the circuit ? a. A- Voltmeter ; V- Ammeter b. A- Amplifier ; V- Photometer c. A- Ammeter ; V- Voltmeter d. A- Anemometer ; V - Voltaic cell 3. ‘H’ is the heat produced in a resistor which is directly proportional to the square of current ( I) for given resistance, resistance ( R) for given current and time ( T) for which the current flows through resistor. Which law explains this statement? a. Ohm's law b. Newton's law c. Faraday's law d. Joule's law 4. Heating effect of electric current is used in a. Fuse b. Electric kettle c. A and B d. None of the above 5. The product of voltage and current is known as a. Power b. Velocity c. Work done d. Gravity 6. Power can be represented in a. V× I b. I2R c. V2R d. All the above 7. When the switch is turned on the conventional current start flowing from the positive terminal to the neg- ative terminal of a battery a. The above statement is invalid b. The above statement is false c. The above statement is true d. The current will not pass in battery 93

PRACTICE SHEET - 6 (PS-6) 8. A current of 0.4 A is drawn by an electric bulb for 10 minutes.Find the amount of electric charge flows through the circuit. a. 300 C b. 200 C c. 230 C d. 240 C 9. The reading of ammeter decreases to one -half when the length of wire is a. Doubled b. Halved c. Remains same d. Increases four times 10. The resistance of a conductor is directly proportional to its a. Length b. Area of cross - section c. Both A and B d. None II. Short Answer Questions. 1. Define ohm's law. Explain the factors affecting resistance. 2. Four equal resistances are connected in series and in parallel. What will be the ratio of resistances? 3. Imagine an electric circuit with a resistance of 20 ohms and 5A of current is flowing in the circuit. Answer the following questions: i. if we increase the resistance of the circuit then heat produced in the resistor increases or decreases? ii.If current moves through a circuit for 3 min and after sometime the current moves through circuit for 30 min. In which case do you think circuit gets hotter? iii. Calculate the heat produced in the above circuit when current passes for 30s? III. Long Answer Questions. 1. Solve the following numericals ( R ) i. An electric heater consumed power of 880 W when heating is at maximum rate 440 W when heating is at minimum rate. The potential is 220V. Calculate the current and resistance in each case. ii. 220 J of heat is produced each second in a 8 ohms resistor. Find the potential difference across the circuit. 94

PRACTICE SHEET - 6 (PS-6) 2. In the given figure resistors are connected in series connection. Observe the figure and answer the ques- tions: Answer the following questions. i. In a series connection which value doesn't change? ii.In the given circuit, R1, R2, R 3, R4 and R 5 are 1, 2, 3, 4 and 5 ohms respectively. What is the total resis- tance of the circuit? iii.Where is series connection applied? iv.What are the disadvantages with series circuit? v. Why do you think batteries are generally connected in series connection? 95

SELF-EVALUATION SHEET Marks: 20 Time: 30 Mins I.  Answer each of these in one word: III.  Answer each of these in about 40-50 words. (3 Marks) (6 Marks) 1. Identify the component of the circuit shown below 2. Which part of the circuit makes a conducting 1. Calculate the equivalent resistance between link between the cell and the bulb. points A and B. 3. How many coulombs of charge are possessed by an electron? II.  Answer each of these in about 20-30 words. (6 Marks) 1. Define electric power. Express it in terms of po- tential difference V and resistance R. 2. State difference between the wire used in the element of an electric heater and in a fuse wire. 3. Out of the two wires A and B shown below, 2. Calculate the resistance of 2 km long copper which one has greater resistance? Justify your wire of radius 2 mm. Specific resistance of cop- answer. per is 1.72 x 10-8Ωm. If the current of 5 A flows through this wire, calculate the voltage applied. 96

SELF-EVALUATION SHEET Marks: 20 Time: 30 Mins IV.  Answer this question in about 70 words. (5 Marks) 1. Explain how the principle of heating effect of elec- tric current is applied in electric bulbs. 97

13. Magnetic Effects of Electric Current Learning Outcomes At the end of this lesson, students will be able to: • Describe the working of an electromagnetic in- • Explain the properties of the magnet under the duction phenomenon. influence of the electric current. • Explain the construction and working of an elec- • Explain the magnetic field lines created by the tric generator. bar-magnet, solenoid and circular loop. • Explain the design of a domestic circuit. • State the right hand and left hand thumb rule. • Describe the current force carried by the magnet. • Explain the constructing and working of an electric motor. Concept Map Magneticceuffrerecnt tof electric Magnetic field Electric circuit for homes Electric motor Conductor Circular loop Solenoid Electric induction Electric generator Key Points • Magnetic field has both direction and magnitude. Field lines are used to represent • Current carrying wire behaves like a magnet. It is a magnetic field. A field line is the path along called magnetic effect of current. which a hypothetical free north pole would tend to move. The direction of the magnetic field at a • A compass is a bar magnet. The ends of the point is given by the direction that a north pole needle point approximately towards south and placed at that point would take. Field lines are north directions. The end pointing towards shown closer together where the magnetic field north is called north pole and the end pointing is greater. towards south is called south pole. • No two field lines cross each other, if they cross • The region surrounding a magnet, in which the it means that at the point of intersection, the force of magnet can be detected, is said to have compass would point towards two directions a magnetic field. The lines along which the iron which is not possible. filings align themselves represent magnetic field 98 lines.

13. Magnetic Effects of Electric Current • When you hold the current carrying conductor in right hand, then direction of the wrapped fingers indicates the direction of the magnetic field around the conductor and thumb indicates the direction of the current. • Magnetic field produced by a current- carrying conductor depends inversely on the distance from it. • The magnet formed due to the electric current is known as electromagnet. • The direction of the force on the conductor depends upon the direction of current and direction of magnetic field. • According to Flemings right hand thumb rule, fore finger and middle finger of the left hand indicates the current and magnetic field respectively while thumb indicates the direction of the motion or the force acting on the conductor when three fingers are held mutually perpendicular to each other. • Electrical motor is a rotating device that converts electrical energy to mechanical energy. • A device that reverses the direction of flow of current through a circuit called a commuter. • A commercial motor consists of different parts like an electromagnet, large number of motors and armature. • As the current in the primary coil changes it induces the magnetic field in the secondary coil it is also known as mutual inductance. • Electric generator is a device which uses mutual inductance phenomena to produce electric current. • In domestic applications, the red insulation is live wire, the neutral wire is made of black insulation. The third wire is grounded and made of green insulation. The potential difference between these two wires is 220V. • To protect house appliances from short circuiting, and from over loads, fuse is used. Key words – current, magnet, electromagnet, poles, generator, motor, fuse, wiring. 99

13. Magnetic Effects of Electric Current Work Plan CONCEPT COVERAGE COVERAGE DETAILS PRACTICE SHEET PS-1 Magnetic effect and field lines • Basic concepts • Magnetic field and field lines PS-2 Magnetic field • Conductor PS-3 • Right hand thumb rule PS-4 • Circular loop PS-5 • Solenoid Self-evaluation Sheet Electric motor and electromagnetic • Force on conductor induction • Flemings left hand rule • Electric motor principle Electric generator and domestic • Generator principle wiring • Domestic electric circuit Worksheet for \"Magnetic Effects of Electric Current\" Evaluation with self- check or Peer check* 100

PRACTICE SHEET - 1 (PS-1) 1. State whether the following statements are true or false: a. Current carrying conductor behaves like a magnet. b. In a compass, needle magnet is used. c. Unlike poles of the magnet repel each other. 2. Define magnetic field and field lines: 3. Fill in the blanks: a. The region surrounding the magnet in which force of the magnet can be detected is called___________. b. The ends of the magnet in a compass needle point indicates ____ and ______ poles. 4. Draw magnetic field lines around a bar magnet: 5. List the properties of magnetic lines of force. 6. Choose the appropriate answer for the following questions: i. Two field lines _______. a. can cross over b. cannot cross over c. sometimes can cross over d. depends on the type of the field ii. The relative strength of the magnet field depends upon a. how far the lines are b. how closeness the field lines are c. depends on situation d. none of the above iii. Magnetic field line is a quantity that has ___. a. both direction and magnitude. b. only direction c. only magnitude d. nor the direction nor magnitude 101

PRACTICE SHEET - 2 (PS-2) 1. State whether the following statements are true or false. a. The magnetic field produced increases along with the current flowing through conductor increases. b. The magnetic field produced by a given current in the conductor decreases as the distance from it increases. c. In right hand thumb rule, the wrapped fingers indicate the direction of the current. d. A strong magnetic field produced inside a solenoid can be used to magnetise a piece of magnetic material. 2. Draw the diagram to represent the uniform magnetic field in a given region. 3. Choose the correct option for each of these statements. i. In a current carrying circular loop, the magnetic field becomes larger as we move a. Away from it b. Near to it c. Constant ii. The pattern of the magnetic field lines around a current-carrying solenoid a. is not same as the bar magnet b. is same as the bar magnet c. depends on the magnetic rule 4. How are magnetic field lines produced by a current carrying conductors in a circular loop? Explain with a diagram. 5. Write a short note on solenoid. 6. What is right hand thumb rule? PRACTICE SHEET - 3 (PS-3) 1. State whether the following statements are true or false. a. The magnetic field produced applies the force on the nearby magnet. b. The direction of the force is reversed when the direction of the current is reversed. 2. State and explain Fleming’s left hand rule. 3. What is an electric motor? Where is it used? 4. Explain the functions of the following parts in an electric motor. a. commutator b. armature c. split ring 5. Explain the construction of an electric motor with a neat diagram. 6. Explain the working of an electric motor with a neat diagram. 7. Explain the electromagnetic induction. 8. Explain the Flemings right hand rule. 9. What are the parts of a commercial motor? 102

PRACTICE SHEET - 4 (PS-4) 1. State whether the following statements are true or false. a. Electric generator works on the principle of electromagnetic induction. b. In domestic wiring, red colour is called passive wire. c. Direct current can flow in multiple directions. d. Grounding of wire is necessary to minimize the shocks. 2. With a neat diagram briefly explain the construction of an electric generator. 3. Explain the working of an AC electric generator.What are the colour coding for the domestic wiring? 4. What are the colour coding for the domestic wiring? 5. Explain the working of DC generator. 6. How is alternating current different from the direct current? 7. Fill in the blanks a. In India, the AC changes its direction for every_______ second. b. The power loss is minimum in _______current. 8. Why is it essential to connect the green wire to the ground? 9. Draw the schematic diagram of the domestic circuit. 10. Explain the wiring of the domestic circuit. 11. Explain the importance of fuse in a domestic circuit. 12. What are the reasons for overloading of a circuit? a. Connecting too many appliances to a single socket. b. Accidental hike in the supply voltage. c. When the insulation of wires is damaged d. Fault in the appliances 103

PRACTICE SHEET - 5 (PS-5) I. Choose the correct option. 1. Who discovered the concept of electromagnetic induction ? a. Michael Faraday b. Sir Isaac Newton c. Michael Jackson d. Alexander Flemming 2. AC generator works on which principle a. Fleming right hand rule b. Electromagnetic induction c. Maxwell's cork screw rule d. Fleming left hand rule 3. Which rule is also called Maxwell’s cork screw rule? a. Fleming right hand rule b. Fleming left hand rule c. Right hand thumb rule d. Lenz rule 4. In Fleming's right hand rule the fore finger indicates a. Force b. Movement of conductor c. Direction of current d. Direction of magnetic field 5. How does the magnetic field line look like at the centre of circular loop? a. Straight line b. Circular loop c. Zigzag d. Curved 6. Type of generator used at power stations. a. DC generator b. AC generator c. Both d. None of the above 7. The device used to reverse the direction of current in the coil of a motor. a. Slip rings b. Coil c. Commutator d. Carbon brushes 8. A current carrying conductor is placed in magnetic field which is anticlockwise to the conductor. If the conductor is placed in East - west direction, what will be the direction of the current ? a. West- East b. North - South c. South - North d. East - West 9. Ria divided a magnet into 3 parts X, Y and Z. Y is the middle part. She wanted to know which part shas maximum and minimum magnetic strength. Can you help her from the options given below a. Maximum at Y & Z ; minimum at X b. Maximum at X and Z; minimum at Y c. Minimum at X and Z ; maximum at Y d. Equal at all places 104

PRACTICE SHEET - 5 (PS-5) 10. The direction of induced e. m. f. can be found by a. Right hand thumb rule b. Fleming law c. Lenz' s law d. Kirchhoff' s law II. Short Answer Questions. 1. What is electromagnetic induction? Give two examples. 2. I am a green colour wire, the metallic body of electrical appliances are connected to me. I am very much friendly to the user. i. Guess who am I? ii. What is the use of me ( wire) iii. How am I ( wire ) user friendly? 3. Read the following paragraph. Answer the questions related to the paragraph. An electric current always produces a magnetic field. Even weak ion currents travel along the nerve cells in our body produce magnetic field. Magnetic field produced in the body is used to catch images of vital organs. i) Which technique is used to obtain images of parts of the body? ii) What is the importance of magnetic resonance in the medical field? iii) What does 'MRI' stand for? III. Long Answer Questions. 1. Answer the following questions. i. Draw magnetic field lines against bar magnet. ii. State the characteristics of magnetic field lines. 2. Analyze and solve the following. I. An electric heater of 2KW power rating is operated in domestic electric circuit that has a current rating of 5A. What happens in this situation? Explain. ii. The given figure shows domestic electric circuit. Study the circuit and list two errors you observe from the circuit. How can you rectify them? iii. Discuss any three safety measures while using electrical appliances connected in domestic electric circuit. 105

SELF-EVALUATION SHEET Marks: 15 Time: 30 Mins other. I. Choose the most appropriate option: 3. The magnetic field lines created by the (2 Marks) solenoid is the same as that of the bar magnet. 1. The AC current in India has frequency V. Answer the following: of_______. a. 100 Hz 1. Explain the magnetic field caused due to b. 50 Hz current carrying in a solenoid. (2 Marks) c. 75 Hz d. 5 Hz 2. In Flemings right hand rule, thumb indicates the __________. a. Current induced in the conductor b. Magnetic field c. Movement of the conductor d. None of the above II. Name the following: (3 Marks) 1. A device which converts electrical energy to mechanical energy. 2. What are the differences between direct and alternating current? (2 Marks) 2. A device which generates electricity. 3. A device which prevents short circuiting. III. Give reasons in one word or in a single sentence for the following statements: (3 Marks) 1. The current flowing in the primary coil produces current in the secondary coil. 2. Fuses are necessary in the domestic wirings. 3. Two separate circuits are used of one 15 A and another 5A in domestic circuits. IV. State whether following statements are true or false: (3 Marks) 1. Current carrying conductor applies magnetic force to the nearby conductor or magnet. 2. Two identical poles in the magnet attract each 106

14. Sources of Energy Learning Outcomes energy resources. • Describe the different types of non-conventional At the end of this lesson, students will be able to: • Describe the features of good source of energy. energy resources applications. • Explain the different types of power plants. • Explain the consequences of the usage of fossil • Explain the different types of conventional fuels fuels. and its applications. • Describe the importance of non-conventional Concept Map Source of Energy Basic Concept of Energy Conventional Energy Non Conventional Energy Consequences • Thermal power plant • Solar energy • Hydro power plant • Tidal energy • Wind Energy • Wave energy • Bio mass, gobar gas etc • Nuclear energy • Geo thermal energy • Ocean thermal energy Key Points • Energy can neither be created nor be destroyed. leads to emission of nitrogen, oxygen etc. Energy is in different forms which can be • From the burning of fossil fuel heat is generated. converted from one to another. Since energy is available in different forms selecting the correct The heat is used to convert water in to steam source of energy. and using steam, turbine is rotated. • The simplest turbine has least moving part rotor • Conventional source of energy is that which and blade assembly through which the turbine we are using from long times example coal, converts the mechanical energy to electrical petroleum and natural gas, wood and etc. energy. • The same principle is used in the thermal power • Fossil is used from long days it is non-renewable plants where heat energy is used to generate energy and we have to conserve them, burning electricity. fossil fuel leads to many problems. It will also 107

14. Sources of Energy • Due to the nuclear fusion, fission energy is generated called nuclear energy. The plant • Hydro power plants are those where kinetic where the nuclear reaction takes place is energy of water is used to generate electricity. called nuclear reactor. In India maximum portion of electric energy is obtained from the hydro power plants. • The harmful radiations are released from the nuclear reaction, like nuclear decay • In order to extract the energy from water etc. Nuclear energy was earlier used for large dams are built and water is stored at destructive purpose s as well. a certain height and when water is released from the higher altitude the potential energy • The buring of fuels releases large amount is converted to kinetic energy. The station of smoke and unwanted pollutants to which converts hydro energy into electrical the atmosphere which leads to many energy is called hydro power plant. consequences, but it is difficult to stop the complete usage, hence pollutions can be • Since it is difficult to get the continuous minimised. supply of wood, the other things such as cow dung, and other various materials are used • The energy which we are using may not last as fuels. These fuels have low efficiency and long and hence should be used carefully we produces lots of smoke. should switch to renewable energy resources. • So improvisation can be done to improve the Key words – Energy, conventional energy, property of these fuels, like charcoals, gobar sources of energy, non-conventional energy, gas etc. consequences. • Gobar gas can be produced in a chamber 108 where due to the anaerobic reaction large compounds will break down into smaller compounds and releases methane, carbon dioxide etc. • Gobar gas consists of large portion of methane and it burns without smoke. It has large heating capacity and can be used to lighting the house and for cooking purpose. • The moving wind consist of kinetic energy and the kinetic energy is used to rotate the wind turbine. The wind turbine is one which converts wind energy into electrical energy. • The wind energy is pollution free energy, but the initial cost of the turbine is high. • Due to the increase in energy demand the energy industry has moved to non- conventional energy sector. Solar energy, tidal energy, wave energy, ocean thermal energy, geothermal energy and nuclear energy. • Solar energy is the source of all forms of energy. Converting solar energy into useful work is called solar energy harvesting. Solar cookers, solar cells, solar water heater are some examples of the solar energy harvesting. • Due to gravitational pull the level of the sea rises and falls. It is called high and low tides respectively. A turbine is fixed to extract the energy from this. • Wave energy is also a form of kinetic energy, where energy is extracted from waves. • Ocean thermal energy is the energy created due to the difference it the temperature. The similar kind of energy is also available in earth called geo thermal energy.

14. Sources of Energy Work Plan CONCEPT COVERAGE COVERAGE DETAILS PRACTICE SHEET PS-1 Basic concept of energy • Introduction PS-2 • Convectional source of energy PS-3 Conventional source of energy • Thermal power plant • Hydro power plant PS-4 • Wind Energy PS-5 • Methods to improve the efficiency of the Self-evaluation Sheet conventional fuels • Solar energy • Tidal energy Wave energy Non-conventional type of energy • Nuclear energy • • Geo thermal energy • Ocean thermal energy Environmental consequences • Environmental effects • Durability of energy sources Worksheet for \"Sources of Energy\" Evaluation with self- check or peer check 109

PRACTICE SHEET - 1 (PS-1) 1. State whether the following statements are true or false. a. Energy can be destroyed. b. The amount of heat liberated after burning determines the quality of the fuel. 2. Explain the characteristics of good fuel 3. State the law of conservation of energy. 4. What are the disadvantages of fossil fuels? 5. Why is 100 percent energy conversion not possible? 6. Explain, why the selection of source of energy depends on the type of applications? PRACTICE SHEET - 2 (PS-2) 1. List out the different types of energies. 2. State whether the following statements are true or false. a. After burning fossil fuels, it release large amount of sulphur and nitrogen. b. In thermal power plants heat energy is converted to steam and steam is used to run the turbine. 3. Choose the incorrect statement from the following. a. In thermal power plants fossil fuels are used. b. In hydro power plant kinetic energy of water is used to run the turbine. c. Bio mass cannot be used as fuel. 4. Explain how thermal power plant works. 5. Explain how kinetic energy of water is used for generating electricity. 6. Explain the construction and working of gobar gas (bio-gas) plant. 7. Explain how wind energy can be extracted. 8. Draw and identify the different parts of a bio gas plant. 9. Match the followings: Source Energy A. Wind Turbine 1. Moving wind B. Thermal power plant 2. Moving water C. Hydro power plant 3. Bio-mass D. Bio-gas plant 4. Coal 10. How can biomass worked as energy source? What are the disadvantages? 11. Bio gas is an excellent fuel. Justify the statement. 110

PRACTICE SHEET - 3 (PS-3) I. Anwer each of these question: 1. Explain why non-conventional energy is gaining importance nowadays. 2. What is solar energy harvesting? 3. How does solar cell panel work? 4. What is tidal energy? How we can harness energy from tides? 5. What is ocean thermal energy? How can it be utilised? 6. Explain how nuclear energy is used to generate electricity? 7. State whether following statements are true or false. a. Nuclear energy can be used for the destructive purpose. b. Solar energy is not a continuous energy. c. Ocean thermal energy is the heat energy available on earth. d. Uranium is nuclear active element. e. Solar energy can be used for cooking purpose. 8. Explain the method of harnessing geothermal energy. II. Fill in the blanks: a. The nuclear energy is obtained by______ reaction. b. The difference in the sea level gives energy called_______. PRACTICE SHEET - 4 (PS-4) I. Answer each of these questions: 1. Name some renewable sources of energy. 2. Why should we be careful while using fossil fuels? 3. State whether following statements are true of false. a. Renewable energy cannot be used for longer period of time. b. Non-renewable energy is exhaustible type of energy resource. c. Fossil fuel use leads to delete environmental pollution. 4. Match the following: 1.Ocean energy A. Fission reaction 2.Wind energy 3.Solar energy B. Solar radiation 4.Nuclear energy C. Energy due to waves D. Blowing wind 111

PRACTICE SHEET - 5 (PS-5) I. Choose the correct option. 1. In these power plants, kinetic energy is produced from water a. Nuclear power plant b. Solar power plant c. Hydroelectric plant d. All the above 2. Trapped heat inside the earth is called a. Hydro electrical energy b. Geothermal energy c. Heat energy d. Solar energy 3. A typical solar cell develops a voltage of a. 3.5 volts b. 10 volts c. 0.5 volts d. 15 volts 4. E = ∆ mc2 ; What is c? a. c is the direction of light b. c is the amount of energy c. c is the mass of the object d. c is the specific heat of the object 5. Which among the following is used as a major energy source for power generation in India ? a. Coal b. Natural gas c. Petroleum d. Solar energy 6. The chemical reaction involved in generation of nuclear power is a. Nuclear mission b. Nuclear explosion c. Nuclear fission d. Nuclear reaction 7. Mars orbiters use this as the main source of energy. a. Nickel cadmium cell b. Solar cell c. Galvanic cell d. Dry cell 8. Which mirror is best suited for solar cooker ? a. Convex mirror b. Plane mirror c. Concave mirror d. None of them 9. The use of turbine in the generator is a. Conducts electricity b. Gives better air circulation c. Increase speed of motor d. Rotates magnet in the generator 112

PRACTICE SHEET - 5 (PS-5) 10. The energy generated from solar energy is DC. To use solar energy for industrial purpose a. Directly DC is used b. DC is converted to AC c. Both a and b d. None II. Short Answer Questions. 1. Why charcoal has higher efficiency as fuel than wood ? 2. ' Green energy - Green environment’. What does this mean ? 3. Answer the following questions. I. Is energy production related to country's economy ? II. What is OTEC? How energy is produced here? III. Give two applications of solar cell. III. Long Answer Questions. 1. Define i) Nuclear energy ii) Chain reaction. Explain what are the peaceful uses and disadvantages of nuclear energy? 2. Observe the figure and answer the following questions. I. What can you depict from the above image? II. With reference to point B how much potential energy is converted into kinetic energy in water reservoir? III. If the channel taking water to turbine starts at point A, what will be the effect of electricity? IV. If the channel taking water to turbine starts at point C, what will be the effect of electricity? 113

SELF-EVALUATION SHEET Marks: 15 Time: 30 Mins I. Choose the most appropriate word: III. Categorize the following into renewable and (4 Marks) nonrenewable energy resources: 1. Solar cell converts _____ to ______. (2 Marks) a. Solar radiation, Electrical energy b. Electric energy, solar radiation a. Solar Energy c. Electrical radiation, solar energy b. Wind Energy d. None c. Ocean Energy d. Petroleum 2. Tidal energy is the energy from __________. e. Coal f. Diesel a. Nuclear reactions b. Waves of the sea IV. Answer the following questions: c. Solar radiation d. none of the above 1. Explain the extraction of any two types of renewable energy. (3 Marks) 3. The energy produced by virtue of differences in the temperature of the ocean surfaces are called as____. a. Ocean thermal energy b. Geo thermal energy c. Tidal energy d. None 4. Generator converts mechanical energy to_______. a. Electrical energy b. Hydro energy c. Wind energy d. Solar energy II. State whether following statements are true or false: (3 Marks) 2. What is the importance of non-renewable 1. The amount of heat liberated determines the energy in the current trend? (3 Marks) quality of the fuel. 2. Blades of the wind turbine needs regular maintenance. 3. Fossil fuels does not contain sulphur and nitrogen. 114

15. Our Environment Learning Outcomes At the end of this lesson, students will be able to: • Describe the causes and effects of pollution, • Define ecosystem. ozone layer depletion and biomagnification. • Describe the components of ecosystem. • List out the examples of biotic and abiotic • Explain the importance of ozone. • Explain the problems caused due to improper components. • Explain the functioning of ecosystem with waste disposal. respect to food chain, food web and trophic levels. Concept Map Our Environment Eco-system Environmental degradation Abiotic component Biotic component Pollution Food chain and Ozone layer food web depletion Biomagnification Key Points concentration of these chemicals gets accumu- lated in our bodies. This phenomenon is known • All the interacting organisms in an area togeth- as biological magnification. er with the non-living constituents of the envi- • Ozone is a combination of 3 atoms of oxygen, ronment form an ecosystem, i.e., the living and and is present in the upper layers of our atmo- non-living things together constitute an ecosys- sphere. It protects us from harmful UV radia- tem. For example, a garden, an aquarium, a for- tions of the sun. est, etc. form an ecosystem. • The amount of ozone is getting depleted slowly due to some harmful chemicals like chloroflu- • In our environment, you can see a series of or- orocarbons (CFCs). UV radiation is highly dam- ganisms feeding on one another, known as food aging to organisms, for example, it is known to chain. For example, a food chain can be repre- cause skin cancer in human beings, and there- sented as: Grass > grasshopper > frog > snake > fore we should take care of ozone layer. eagle. • The waste, we generate may be biodegradable or non-biodegradable. • One organism is eaten by more than one or- • The disposal of the waste, we generate is caus- ganism, which in turn are eaten by several oth- ing serious environmental problems. er organisms. So instead of a straight line food . chain, the relationship can be shown as a series Key Words – Bio magnification, ecosystem, abi- of branching lines called a food web. otic, biotic, CFC, ozone, UV radiations, Pollution, Food chain, Food web. • We are actively using pesticides and other chemicals these days for increasing our crop 115 yield. When these crops or plants are consumed by consumers, these chemicals end up accumu- lating in their bodies. As human beings occupy the top level in any food chain, the maximum

15. Our Environment Work Plan CONCEPT COVERAGE COVERAGE DETAILS PRACTICE SHEET SIMULATION/ Eco-system PS-1 VIDEO Environmental • Biotic and abiotic factors degradation • Food chain PS-2 Food Chain • Food web • Trophic levels • Pollution • Ozone layer depletion • Bio-magnification • Waste generation and disposal Worksheet for \"Our Environment\" PS-3 Evaluation with self- Self-evaluation check or Peer check* Sheet 116

PRACTICE SHEET - 1 (PS-1) I.  Choose the correct alternatives to complete the sentences. 1. The functional unit of environment is a. Ecosystem b. Nitrogen c. Carbon d. Oxygen 2. Which of the following is an not example of abiotic factors? a. Light b. Plants c. Heat d. Temperature 3. _______ is an omnivore animal. a. Lion b. Hawk c. Jackal d. Man 4. Each stage in food chain is called a/an a. photon level b. phantom level c. trophic level d. energy level 5. In a food chain, organisms a. feed on preceding one b. provides food for succeeding organisms c. provide more energy for the next trophic level d. both A and B II.  Answer each of these questions. 1. Define ecosystem. 2. List out the components in a food chain 3. Write any two examples of artificial ecosystem. 117

PRACTICE SHEET - 2 (PS-2) I . Choose the correct alternatives to complete the sentences. 1. Which of the following is a biodegradable substance? a. Glass b. Plants c. Plastics d. Polythene 2. The number of atoms of oxygen present in ozone are a. 3 b. 4 c. 2 d. 1 3. Accumulation of non-biodegradable pesticides in the food chain in increasing amount at each higher trophic level is known as a. Eutrophication b. Pollution c. Biomagnification d. Accumulation 4. Depletion of ozone is mainly due to a. Chlorofluorocarbon compounds b. Carbon monoxide c. Methane d. Pesticides II.  Answer each of these questions. 1. How does ozone protect life on the earth? 2. What initiative was taken by UNEP to control ozone layer depletion? 3. Distinguish between biodegradable and non-biodegradable waste. 118

PRACTICE SHEET - 3 (PS-3) I. Choose the correct option. 1. Ozone layer protects us from a. Infrared radiation b. Ultraviolet radiation c. Gamma radiation d. Beta radiation 2. In an ecosystem bacteria are a. Producers b. Consumers c. Decomposers d. Predators 3. Given here are abiotic factors. Pick odd one out. Sunlight, Weather, Water, Plants a. Sunlight b. Weather c. Water d. Plants 4. The number of oxygen atoms present in ozone a. Three b. Two c. Zero d. Five 5. Assume if deer is missing in the food chain given below? Grass → Deer → Tiger a. The population of tiger increases b. The population of grass decreases c. Tiger will start eating grass d. The population of tiger decreases and the population of grass increases 6. An example for non -biodegradable substance a. Animal debris b. Plants c. Plastic d. Leather 7. When residues of chemicals gets accumulated in fruits and vegetables, the phenomenon is called a. Bioaccumulation b. Bioremediation c. Biodegradation d. Biomagnification 8. In the given food chain, suppose the amount of energy at the fourth trophic level is 5 kJ , what will be the energy level at the first trophic level Grass → Grasshopper → Frog → Snake → Hawk a. Remains same b. 500 kJ c. 50kJ d. 5000kJ 119

PRACTICE SHEET - 3 (PS-3) 9. Flow of materials in ecosystems is P and flow of energy in ecosystem is Q. Find out P and Q. a. P- unidirectional ; Q- Cyclic b. P- Cyclic ; Q- Unidirectional c. P- multidirectional ; Q- bidirectional d. P- Cyclic ; Q- bidirectional 10. World Environment Day is observed on a. January 31st b. August 25th c. June 5th d. October 31st II. Short Answer Questions. 1. Answer the following questions. a. Suggest few important modes of waste disposal. b. What is 10 percent law. 2. Energy is produced at every trophic level. Where does the energy go finally? 3 . Give reason why energy flow is unidirectional in ecosystems. III. Long Answer Questions. 1. Explain the phenomenon of “biological magnification” How does it affect organisms belonging to different trophic levels particularly the tertiary consumers? 2. Read the passage and answer the following questions. Sheena collected kitchen waste from her house. The items include spoiled food, vegetable peels, tea leaves, milk packets, polythene covers, newspaper, broken foot wear. All these items were dumped into a flower pot and she covered the pot with soil and sprinkled a little water. After 15 days she observed them. I. What could have happened to the items beneath soil? II. What are the materials which changed their form and structure over the time? III. What are the materials that remain over unchanged for long periods of time? IV. Of these materials, that are changed which ones will change fast? V. Which biotic component is responsible for the changes? 120

SELF-EVALUATION SHEET Marks: 20 Time: 30 Mins I . Answer each of these in one or two words: (3 Marks) 1. Which chemicals degrade the ozone layer? 2. What represents the interlinking of several food chains? 3. What portion of energy is available for transfer from one trophic level to the next trophic level? II.  Answer each of these in about 20-30 words. (6 Marks) 1. Write two points of difference between ozone and oxygen. 2. What will be the consequence of the absence of decomposers in an ecosystem? 3. Why is energy flow in an ecosystem unidirectional? III. Answer each of these in about 40-50 words. (6 Marks) 1. What is biomagnification? 2. In the given food chain, suppose the amount of energy at fourth trophic level is 5 kJ, 5what will be the energy available at the producer level? IV. Answer this question in about 70 words. (5 Marks) 1. i. How is ozone formed? Explain with the help of balanced chemical equation. ii. State the importance of UV rays to the living beings on the earth. 121

16. Sustainable Management of Natural Resources Learning Outcomes • Describe the importance of dams. • Enlist the disadvantages of dams. At the end of this lesson, students will be able to: • Explain different types of rainwater harvesting. • State the importance of natural resources. • Elaborate the importance of fossil fuels. • Explain 3R method of waste management. • List out the negative consequences of over-using • Explain the importance of forest and wild life. • List out the types of stakeholders of forests. the fossil fuels. • Define sustainable management of natural re- • Suggest measures to minimize fossil fuel usage. sources. Concept Map Management of natural resources Laws of Chemical Combination Water resources Coal and petroleum Sustainable management of Water harvesting Alternative sources of energy forest of wildlife Key Points • Combustion of coal and hydrocarbons release a large amount of carbon monoxide, carbon • Natural resources are the resources provided to dioxide, sulphur dioxide, oxides of nitrogen, us by nature soil, air, water, forests, wildlife, coal etc. These cause air pollution and cause various and petroleum are used by man for his survival. diseases like respiratory and throat problems, congestion etc. • Sustainable development is the economic development that is conducted without Key words– natural resources, sustainable depletion of natural resources. management, stakeholders, 3R, water harvesting, coal, petroleum • Forests are biodiversity hotspots. • Chipko Andolan is the movement originated in 122 Garhwal in early 1970s that was the result of a grassroot level effort to end the alienation of people from their forest. • Irrigation methods like dams, tanks and canals have been used in various part of India. • Water harvesting is a method of collection of rain water and its utilisation for various purposes. • Coal and petroleum are non-renewable natural resources.

16. Sustainable Management of Natural Resources Work Plan CONCEPT COVERAGE COVERAGE DETAILS PRACTICE SHEET PS-1 Our resources • Importance of nature resource & • 3R method of waste management PS-2 • Effects of human activities on forest and wildlife Forest and wildlife • Uses of forest resources PS-3 • Conservation of forest resources Self-evaluation Sheet Water resource and coal • Sustaianble management of forest resources and petroleum • People’s participation in forest conservation • Importance of water resources • Importance of dams • Social and environmental issues of dams • Water harvesting • Groundwater recharge • Importance of groundwater • Environmental consequences of using fossil fuels • Measure to conserve fossil fuels Worksheet for \"Sustainable Management of Natural Resources\" Evaluation with self- check or peer check 123

PRACTICE SHEET - 1 (PS-1) I. Choose the most appropriate alternative for each of these statements. 1. Floods can be prevented by a. Afforestation b. Removing top soil c. Deforestation d. Agriculture 2. ‘Bidis’ are made of ____ leaves. a. Neem b. Tendu c. Tamarind d. Pine 3. _____ community in Rajastan has played an important role in protecting the forests. a. Pindari b. Bishnoi c. Kalkeya d. Singhali 4. Measure of biodiversity of an area is a. The number of species found there b. The range of different life forms c. Both (a) and (b) d. None of these. 5. The Chipko movement started from: a. Reni in Garhwal b. Arborio forest c. Khejrali village d. None of these 6. The concept of sustainable development encourages a. Form of growth that meets current basic needs b. Preservation of the resources for the need of future generation c. A change in all respects of life d. All the above II. Answer each of these questions: 1. What do you mean by the term sustainable development? 2. Who are the various stakeholders of forests? How are they dependant on the forest? 3. Give an example of monoculture. How does monoculture impact the biodiversity? 4. What is chipko movement? 5. Write any one advanatage of re-use over recycle. 6. What are the possible consequences of deforestation on the environment? 124

PRACTICE SHEET - 2 (PS-2) I. Answer each of these questions: 1. Why do we seek to build dams? 2. What is the aim of watershed management? 3. Enlist the possible social and environmental consequences of builiding dams. 4. How does overuse of fossil fuels lead to global warming? 5. Which gases are released as a result of combustion of fossil fules? 6. Describe the water harvesting system built along a largely level terrain. 7. List out any four simple choices that can be made in our dialy lives to conserve fossil fuels. 125

PRACTICE SHEET - 3 (PS-3) I. Choose the correct answer. 1. In these power plants, kinetic energy is produced from water a. Nuclear power plant b. Solar power plant c. Hydroelectric plant d. All the above 2. Trapped heat inside the earth is called a. Hydro electrical energy b. Geothermal energy c. Heat energy d. Solar energy 3. A typical solar cell develops a voltage of a. 3.5 volts b. 10 volts c. 0.5 volts d. 15 volts 4. E = ∆ mc2 ; What is c? a. c is the direction of light b. c is the amount of energy c. c is the mass of the object d. c is the specific heat of the object 5. Which among the following is used as a major energy source for power generation in India ? a. Coal b. Natural gas c. Petroleum d. Solar energy 6. The chemical reaction involved in generation of nuclear power is a. Nuclear mission b. Nuclear explosion c. Nuclear fission d. Nuclear reaction 7. Mars orbiters use this as the main source of energy. a. Nickel cadmium cell b. Solar cell c. Galvanic cell d. Dry cell 8. Which mirror is best suited for solar cooker ? a. Convex mirror b. Plane mirror c. Concave mirror d. None of them 9. Which community of Rajasthan has religious belief of conserving forests? a. Vaishnaoi b. Chenchu c. Bishnoi d. Rajputs 126

PRACTICE SHEET - 3 (PS-3) 10. Consider the following statements related to the Sustainability Development. I. It refers to a process or state that can be maintained indefinitely. II. Natural resources must be used in ways that do not create ecological debts by over exploiting the carrying and productive capacity of the earth. III. A minimum necessary condition for sustainability is the maintenance of the total natural capital stock at or above the current level. a. Only I b. Only II c. Only II & III d. I, II & III II. Short Answer Questions. 1.Can you guess the consequences of depletion of natural resources? 2. Answer the questions. I. What are fossil fuels? II. List uses of coal and petroleum. 3. Write five slogans to promote conservation of natural resources. III. Long Answer Questions. 1. 'Narmada bachao andolan' was related to which dispute? Discuss the advantages and disadvantages of dams. 2. What are Euro norms? Explain Euro I and II norms. 127

SELF-EVALUATION SHEET Marks: 15 Time: 30 Mins I. Choose the correct answer: 2. What are natural resources? State two factors that work against an equitable distribution of (4 Marks) these resources. 1. Which of the following is a greenhouse gas? (3 Marks) a. Nitrogen dioxide 3. What is meant by wildlife conservation? Why is b. Sulphur dioxide wildlife important to us? c. Carbon dioxide (3 Marks) d. Carbon monoxide 2. What is coliform? a. Bacteria b. Virus c. Fungi d. Disease 3. Water pollution can be identified by testing its a. pH level b. Biological Oxygen Demand (BOD) c. Both (a) and (b) d. None of these. 4. Which energy of water is used to produce hydroelectricity? a. Potential energy b. Kinetic energy c. Both (a) and (b) d. None of these. II. Answer each of these questions: 1. Explain the 3R of waste with an example. (5 Marks) 128



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