202110222-TRIUMPH-STUDENT-WORKBOOK-SCIENCE-G06-PART2

Science Workbook_6_P_2.pdf 1 11/5/19 5:39 PM Name: ___________________________________ Section: ________________ Roll No.: _________ School: __________________________________

Table of Contents 1 23 12 SIMPLE ELECTRIC CIRCUITS 53 13 LEARNING HOW TO MEASURE 79 14 MOVEMENTS IN ANIMALS 105 15 LIGHT, SHADOWS AND IMAGES 16 LIVING AND NON-LIVING 129 PROJECT BASED PRACTICE QUESTIONS TABLE OF CONTENTS

12. SIMPLE ELECTRIC CIRCUITS SESSION 1 CELL, BULB, THE STORY OF BULB 1.1 Mind Map SESSION 1. CELL, BULB, THE STORY OF BULB 1

1.2 Terminology i. Electricity – A form of energy resulting from the existence of charged particles. ii. Electric cell – A device, such as a battery, that is capable of changing some form of energy, such as chemical energy or radiant energy, into electricity. iii. Light bulb –A light–emitting device that consists of a gas–filled glass tube which is used inside electric light fixtures and flashlights. iv. Terminals –A point of connection for closing an electric circuit. v. Filament –A conducting wire. 1.3 Key Concepts i. A cell is a cylindrical metal can filled with chemicals and capable of generating elec- trical energy. ii. It has got a protrusion towards one end, that terminal is called as positive terminal and opposite to it is negative terminal. iii. A bulb is a device capable of converting electricity into light. iv. It consists of two terminals and a filament. It glows and emits light. SESSION 1. CELL, BULB, THE STORY OF BULB 2

1.4 Conceptual Understanding Q1. In a bulb, the part which gives us light is [Refer to TB page 120 Q3] a) Metal base b) Glass chamber c) Filament d) Terminals. A. In a bulb, the filament gives us light. 1.5 Appreciation and Aesthetic Sense, Values Q1. You have studied the story of Thomas Alva Edison. Write a note appreciating his efforts in inventing the bulb. [Refer to TB page 121 Q11] A. i. Many scientists worked hard for many years before Edison for inventing a bulb but no one succeeded. Eventually, Thomas Alva Edison was the first scientist who succeeded in inventing the light bulb. ii. Edison invented a bulb which could work effectively for a number of days. iii. We appreciate his genius, intelligence, diligence and patience which lead to this important invention, thereby influencing our lives in an important way. iv. Edison was inquisitive in nature and had learned science by performing experiments himself. v. Like him, we must also keep the curiosity and inquisitiveness alive in our learning for a better understanding. Q2. If you put the switch on, a light will glow, a fan will rotate, an iron box heats up etc. All these different functions will be performed by electricity. How do you feel about the comforts given by this great invention to human beings? [Refer to TB page 121 Q13] A. 1) Electric energy is the type of energy that can be converted into any form of energy. 2) With the efforts of many scientists, this energy has been tamed to provide comfort to us through various electronic appliances. SESSION 1. CELL, BULB, THE STORY OF BULB 3

3) Due to our dependence on electricity, a number of scientists are presently struggling to generate electricity from various natural and renewable resources of energy. 4) This great invention has revolutionised the life style of human beings, making it easier and more comfortable. 1.6 Application to Daily Life, Concern to Bio Diversity Q1. List the daily activities in which we use electricity. [Refer to TB page 121 Q12] A. i. From dawn to dusk and even during night, we make use of electricity. ii. We use the electric geyser/Heating rod to get hot water for bathing. iii. Electricity is used to run the mixers/grinders in the kitchen. iv. Fans, air coolers and air conditioners keep us comfortable in the hot summer days. They also run on electricity. v. We use refrigerators to keep the food materials cold and to make ice creams or to prevent them from melting. vi. Television and DVD’s, computers etc. all need electricity to run. vii. These days, even electric bikes and cars are used which run on battery. viii. Electricity is also used in industries to run big machines. Q2. Write a list of electrical appliances in your house. Classify them as follows. [Refer to TB page 121 Q14] A. Works with Works with Works with both cell cseolluarcsea electaricsocuurrcreent as and elecstoriucrccuerrent as Torch light Electric bulb Tape recorder Remote of a Television Transistor radio TV Flood Lights Electric Piano Electric scooter Electric Grinder Piano Wall clocks SESSION 1. CELL, BULB, THE STORY OF BULB 4

SESSION 2 SIMPLE ELECTRIC CIRCUITS, WHAT IS A CIRCUIT, SWITCH, TORCH LIGHT 2.1 Mind Map SESSION 2. SIMPLE ELECTRIC CIRCUITS, WHAT IS A CIRCUIT, SW... 5

2.2 Terminology i. Electric circuit – An electric circuit is a closed path in which current flows. ii. Open circuit –When current does not flow through a circuit, the circuit is called open circuit. iii. Closed circuit – When current flows through a circuit, the circuit is called a closed circuit. iv. Conducting wire –is a metal conductor that carries electricity over a distance. SESSION 2. SIMPLE ELECTRIC CIRCUITS, WHAT IS A CIRCUIT, SW... 6

v. Appliance – A device or piece of equipment designed to perform a specific task. vi. Battery – A container consisting of one or more cells, in which chemical energy is converted into electricity and used as a source of power. vii. Switch –A device which is used to break an electric circuit is called switch. 2.3 Key Concepts i. Electricity flows in a closed path known as circuit. ii. A cell (power source), a bulb and connecting wires make a simple circuit. iii. In our houses, two electric supply wires namely live and neutral are connected to the two terminals of the bulb through a switch. iv. Electric switch is an arrangement to close or open (break) an electrical circuit by allowing or breaking the electricity flow in the circuit. 2.4 Conceptual Understanding Q1. What is an electric circuit? Explain with a diagram. [Refer to TB page 120 Q1] A. i. Source of electricity, an appliance, and a switch connected with an electric con- ducting wire together forms an “ electric circuit ”. ii. Source of electricity (battery), an electronic appliance (bulb) and a switch are con- nected by a wire as shown in the figure. iii. Using battery as a source of electricity, the bulb glows when we switch on the circuit. iv. Switch is used to open and close the circuit. SESSION 2. SIMPLE ELECTRIC CIRCUITS, WHAT IS A CIRCUIT, SW... 7

Q2. What are the parts of a torch light? [Refer to TB page 120 Q2] A. The parts of a torch light are 1) Hollow cylindrical barrel 2) Torch cells 3) Bulb 4) Glass cover 5) Reflector 6) Switch 7) Metal spring Q3. What will happen if the cells in a torch are arranged as shown in the following figure? Why? [Refer to TB page 121 Q8] A. The torch light will not glow if the cells in a torch are arranged like this. Because to complete the circuit ‘+ve’ and ‘–ve’ terminals are to be connected in order. The correct arrangement should be like this. 2.5 Asking Questions and Making Hypothesis Q1. A circuit is connected with a cell, bulb and a switch. But the bulb is not glowing. Write all possible reasons for this. [Refer to TB page 121 Q10] A. A circuit is connected with a cell, bulb and a switch. But the bulb is not glowing. The reasons may be 1) The bulb could be faulty. 2) The connections in the circuit could be wrong. 3) The cell could be faulty and not working. SESSION 2. SIMPLE ELECTRIC CIRCUITS, WHAT IS A CIRCUIT, SW... 8

2.6 Experimentation and Field Investigation Q1. In activity 4, we observed some situations where the torch bulb glows. Niharika chal- lenged her friends that she could make the bulb not glow even with the cells kept in proper position. What would she have done? [Refer to TB page 121 Q6] A. 1) The lid of the torch might not be tightly screwed, leaving the circuit open. So the bulb does not glow. 2) Niharika might have put an insulator in between the two cells. 3) The switch lever might have been bent in such a way that it did not touch the bulb, making the circuit open. Q2. Connect a circuit as shown in the following diagram [Refer to TB page 121 Q7] a) Does the bulb glow? Why? b) Draw the circuit so that the bulb glows. A. a) The bulb does not glow because the connections in the circuit have been made wrong. The +ve terminal of cell A should be connected to –ve terminal (bottom) of second cell. And, the +ve terminal of second cell should be connected to the bulb. b) SESSION 2. SIMPLE ELECTRIC CIRCUITS, WHAT IS A CIRCUIT, SW... 9

Q3. Connect circuits as shown in the following figure. Write your observation in each case. [Refer to TB page 122 Q15] A. 1. Bulb will not glow because like terminals of batteries are connected together. 2. Bulb will glow because the circuit is closed. 3. Bulb will glow because the circuit is closed. 4. Bulb will glow because the circuit is closed. 2.7 Communication Through Drawing and Model Making Q1. Draw a circuit diagram showing a cell, switch and a bulb. [Refer to TB page 121 Q9] A. SESSION 2. SIMPLE ELECTRIC CIRCUITS, WHAT IS A CIRCUIT, SW... 10

SESSION 3 CONDUCTORS AND INSULATORS 3.1 Mind Map 3.2 Terminology i. Conductor – A material through which electric current can pass. ii. Insulator – A substance or device which does not readily conduct electricity. iii. Metal – A solid material which is typically hard, shiny, malleable, fusible, and ductile, with good electrical and thermal conductivity. iv. Non–metals – An element or substance that is not a metal. 3.3 Key Concepts i. On the basis of property of a substance to allow the passage of electricity through them, they can be classified as conductors and insulators. ii. Conductors are those substances which allow electric current to flow through them such as copper, iron etc. iii. Substances which do not allow electric current to flow through them are insulators. Example rubber, wood etc. SESSION 3. CONDUCTORS AND INSULATORS 11

iv. Invention of many electrical devices mark our history. These includes invention of electric bulb by Thomas Alva Edison and electric generator by Michael Faraday. 3.4 Conceptual Understanding Q1. Classify the following into conductors and insulators: [Refer to TB page 120 Q4] Water, Plastic pen, Pencil lead, Dry cotton cloth, Wet cotton cloth, Dry wood, Wet wood A. S. No. Material Conductor Insulator 1. Water x √ 2. Plastic pen x √ 3. Pencil lead √ x 4. Dry cotton cloth x √ 5. Wet cotton cloth √ 6. Dry wood x x √ 7. Wet wood √ x Note: Pure water is a bad conductor of electricity, whereas light impurity in it makes it a good conductor. Generally water we get is impure; so here water acts as good conductor of an electricity. Q2. Match the following. [Refer to TB page 122 Q16] SESSION 3. CONDUCTORS AND INSULATORS 12

Group – A Group – B 1. Conductor A) Cell 2. Source of electricity B) Switch 3. Filament C) Safety pin 4. To close or open a circuit D) Eraser 5. Insulator E) Glowing of bulb A. Group – A Group – B 1. Conductor C) Safety pin 2. Source of electricity A) Cell 3. Filament E) Glowing of bulb 4. To close or open a circuit B) Switch 5. Insulator D) Eraser 3.5 Asking Questions and Making Hypothesis Q1. Niharika observed an electrician repairing a street light wearing gloves on his hand. She asked him some questions. What would be those questions? [Refer to TB page 122 Q5] A. The questions Niharika asked the electrician would probably be: (1) The gloves you are wearing on your hands appear to be different; with what material are they made up of? (2) Why do you wear gloves made up of that particular material? (3) Don’t you experience an electric shock, if you wear those gloves? (4) What are the other materials the gloves can be made of, so that we do not get an electric shock? SESSION 3. CONDUCTORS AND INSULATORS 13

—— CCE Based Practice Questions —— AS1-Conceptual Understanding ] Very Short Answer Type Questions 1. State true or false. [Refer to Session 12.1 ] (i) A bulb should never be touched when electricity is passed through it. [ (ii) William Gilbert was the first person to use the word electricity. [ ] (iii) A cell is a triangular object. [] (iv) In a bulb the two terminals touch each other. [] 2. Answer the following questions in one sentence. [Refer to Session 12.1 ] (v) Who discovered static electricity? (vi) In olden days, what was believed to be the cause of electricity? CHAPTER 12. SIMPLE ELECTRIC CIRCUITS 14

(vii) What do the (+) and (–) signs on a cell indicate? Short Answer Type Questions 3. Answer the following questions in 3-4 sentences. (i) [(Session 12.1)] What was the mistake that Niharika realised when the torch wasn’t working? How did she rectify it? (ii) [(Session 12.1)] Describe a cell. CHAPTER 12. SIMPLE ELECTRIC CIRCUITS 15

Long Answer Type Questions 4. Answer the following questions in 6-8 sentences. (i) [(Session 12.1)] Write short notes on bulb. AS2-Asking questions and making hypothesis Long Answer Type Questions 5. Answer the following questions in 6-8 sentences. (i) [(Session 12.2)] Raju doesn’t know what a torch is. When he saw a torch for the first time, he had some questions. What might these questions be? CHAPTER 12. SIMPLE ELECTRIC CIRCUITS 16

AS3-Experimentation and field investigation Long Answer Type Questions 6. Answer the following questions in 6-8 sentences. (i) [(Session 12.3)] Design an experiment to identify conductors and insulators. 7. Answer the following questions in 6-8 sentences. (i) [(Session 12.1)] On a visit to a factory your teacher identified certain materials as conductors and insulators. How can you describe the two based on your observation. Give examples of each. CHAPTER 12. SIMPLE ELECTRIC CIRCUITS 17

AS4-Information skills and projects Long Answer Type Questions 8. Answer the following questions in 6-8 sentences. (i) [(Session 12.2)] Collect the information about electricity and the working of electric appliances in our houses. CHAPTER 12. SIMPLE ELECTRIC CIRCUITS 18

AS5-Communication through drawing and model making Long Answer Type Questions 9. Answer the following questions in 6-8 sentences. (i) [(Session 12.2)] Draw a well labelled diagram of the inside view of a torch light. CHAPTER 12. SIMPLE ELECTRIC CIRCUITS 19

AS7-Application to daily life, concern to bio diversity Long Answer Type Questions 10. Answer the following questions in 6-8 sentences. (i) [(Session 12.3)] Discuss the daily life examples where we come across conductors and insulators. Objective Questions (B) –ve terminal AS1-Conceptual Understanding (D)Glass chamber 11. Choose the correct answer. . (i) part of the bulb glows. (B) copper (A) +ve terminal (C) Filament (ii) Electric wires are often covered with (A) plastics CHAPTER 12. SIMPLE ELECTRIC CIRCUITS 20

(C) aluminium (D) iron (iii) named the two kinds of electric charge. (A) William Gilbert (B) Benjamin Franklin (C)Thales of Miletus (D)Luigi Galvani (iv) An experiment with which animal lead to the belief that electricity is made inside animals’ bodies? (A) Rat (B) Rabbit (C) Frog (D) Dog (v) Who discovered that electricity could make magnetism? (A) Christian Oersted (B) William Gilbert (C)Luigi Galvani (D)Thales Miletus (vi) Who discovered the electric generator? (A) Thomas Faraday (B) Michael Faraday (C)Christian Oersted (D)Benjamin Franklin (vii) is a good conductor of electricity. (A) Metal (B) Wood (C) Plastic (D) Rubber (viii) The world’s first experimental electric power plant was opened in . (A) USA (B) England (C) India (D) Germany CHAPTER 12. SIMPLE ELECTRIC CIRCUITS 21

(ix) Filaments in bulbs are made of . (A) Copper (B) Silver (C) Aluminium (D) Tungsten (x) Electricity requires a for it to flow. (A) open path (B) closed path (C)neutral path (D)no path CHAPTER 12. SIMPLE ELECTRIC CIRCUITS 22

13. LEARNING HOW TO MEASURE SESSION 1 MEASURING LENGTHS, STORY OF SCALE 1.1 Mind Map SESSION 1. MEASURING LENGTHS, STORY OF SCALE 23

• Metre not a convenient unit for measuring large distances • A large unit called KILOMETRE was defined • One Kilometre is 1000 times larger than a metre • 1 Kilometre =1000 metres SESSION 1. MEASURING LENGTHS, STORY OF SCALE 24

1.2 Terminology i. Measure –To find out the size, amount, or degree of (something) by using an instru- ment or device marked in standard units. ii. Standard unit – A unit of measurement is a definite magnitude of a physical quan- tity, defined and adopted by convention or by law, which is used as a standard for measurement of the same physical quantity. iii. Foot span – Foot span is the distance covered in an average step, either from heel to heel or toe to toe. iv. Hand span – The maximum distance between the tips of the thumb and little finger, taken as the basis of a measurement equal to 9 inches. v. Cubit – An ancient measure of length, approximately equal to the length of a forearm. vi. Metre –The fundamental unit of length in the metric system, equal to 100 centimetres or approximately 39.37 inches. 1.3 Key Concepts i. We come across many examples of measurement in our daily life. ii. To obtain lengths, width, height, area, volume etc., of any object we need to get their measurements. iii. Traditionally, people used hand span, foot span and cubit as units of measurement. But the measurement was not accurate. iv. Units of measurement also varied from person to person or country to country. v. People decided to use the distance between the nose and the tip of the middle finger of their king as a measure. They called this distance one yard. vi. To get an accurate and uniform measurements standard units are required. vii. A standard unit of measurement is necessary to be adopted all over the world. viii. France decided that a certain length of rod made of a special material (Platinum–Iridium) would be called a metre. This is now the accepted standard unit of length worldwide. 1.4 Conceptual Understanding Q1. What is the smallest distance that you can measure with a centimeter scale? [Refer to TB page 135 Q1] A. Millimeter is the smallest distance that we can measure with a centimeter scale. SESSION 1. MEASURING LENGTHS, STORY OF SCALE 25

SESSION 2 MEASURING LENGTH ACCURATELY, MEASURING SMALL THICKNESS 2.1 Mind Map SESSION 2. MEASURING LENGTH ACCURATELY, MEASURING SMALL TH... 26

2.2 Terminology i. Height –It is the distance from the bottom of the feet to the top of the head in a human body, standing erect. ii. Straight path –Continuing in the same direction without deviating. iii. Curved path – A continuously bending line, without angles. iv. Parallax error –It is a displacement or difference in the visible position of an object viewed along two different lines of sight, and is measured by the angle or semi–angle of inclination between those two lines. 2.3 Key Concepts i. In Paris, the capital of France, a certain length of rod made up of an alloy of platinum and Iridium is taken as the standard measure and is called a “metre”. ii. The meter scale is internationally accepted instrument for measuring lengths. One meter (m)=100 centimetres (cm). iii. One centimetre = 10 millimetres (mm). iv. Meter can be used as a standard unit of measuring length for shorter distances how- ever for longer distance kilometre is used. 1km=1000m. SESSION 2. MEASURING LENGTH ACCURATELY, MEASURING SMALL TH... 27

v. We use different instruments like plain tape, roller tape, and centimetre scales of different sizes made of wood, plastic or metal. vi. The error that creeps in due to keeping of eye not perpendicularly to the exact division on the scale is called parallax error. vii. The length of curved lines can be measured by using a thin thread. 2.4 Conceptual Understanding Q1. Are we able to measure the thickness of a metal wire using a scale? Explain. [Refer to TB page 135 Q2] A. i. It is not possible to measure the thickness of a metal wire using a scale. ii. But taking the metal wire in the form of loops we can find the thickness. iii. Eg. Let the number of loops be ‘5’. The corresponding length on the scale is ‘3’ cm. Then the thickness of wire = Length on the scale/Number of loops = 3/5 = 0.6 cm. 2.5 Asking Questions and Making Hypothesis Q1. Make a visit to Panchayat Office, collect information how VRO (Village Revenue Officer) measures areas of agricultural lands in your village. Prepare a questionnaire for this. [Refer to TB page 137 Q14] A. The VRO measures areas of agricultural lands by noting the distances of certain points using a survey chain. He divides the shape of the irregular field into a number of trapez- iums and triangles and by adding the areas of all the figures, he determines the area of the land. The questions in the questionnaire would be: (1) By which instrument does he measure the area? (2) Why does he find the area of the land? (3) What is the reason for dividing the land into trapeziums and triangles? (4) In which unit does he expresses the area? SESSION 2. MEASURING LENGTH ACCURATELY, MEASURING SMALL TH... 28

2.6 Experimentation and Field Investigation Q1. The distance between numbers in a clock is accurately same. List out the things that you observe in your surroundings with accurate distance between them. [Refer to TB page 137 Q16] A. The distance between the numbers in a clock is accurately same. Other things from our surroundings with numbers marked at equal space between them are: (1) Clinical thermometer (2) The scale in my geometrical instrument box (3) Weighing machine (4) A vertical wooden scale used to record our heights 2.7 Appreciation and Aesthetic Sense, Values Q1. A carpenter who makes wooden furniture needs accuracy in measurements. Do you ever notice how he measures? How would you appreciate him? [Refer to TB page 137 Q13] A. 1) A carpenter takes measurements very accurately and nearest to a millimeter. 2) As the carpenter is a practical worker, any wrong measurement taken will affect the furniture he is making. 3) The carpenter puts his mind and concentration on the measurements as his quality of work depends on these measurements. 4) The carpenter takes measurements with a metal tape. SESSION 2. MEASURING LENGTH ACCURATELY, MEASURING SMALL TH... 29

SESSION 3 MEASUREMENT OF AREA 3.1 Mind Map SESSION 3. MEASUREMENT OF AREA 30

3.2 Terminology i. Regular surface – A smooth surface. ii. Irregular surface –Surface which is not levelled or flat or symmetrical. iii. R ectangular body –A body with four sides, four right angles, and two pairs of parallel sides and unequal adjacent sides. iv. Graph paper –Paper printed with a network of small squares to assist the drawing of graphs or other diagrams or calculating area. 3.3 Key Concepts i. Area of closed figures or solid surfaces having the shape of a square or rectangle can be obtained by using the formulae (i) Area of square = side x side (ii) Area of rectangle = length x breadth ii. The units of area are : square centimeter (cm2 ) and square meter (m2 ) iii. Square centimeter is a standard unit of measuring the area of a surface. iv. The area of an irregular plane figure can be measured by using a standard graph paper. v. We use metre as a unit of length and subsequently, centimeters and millimeters as smaller units of length. 3.4 Conceptual Understanding Q1. A school hall measures 20 m in length and 15 m in breadth. Find its area. [Refer to TB page 136 Q3] A. (1) As per the given measurements, it is evident that the shape of the hall is a rectangle. (2) The area of a rectangle = Length x Breadth Length of hall = 20 m; Breadth = 15 m (3) The area of the hall = 20 m x 15 m = 300 m2 SESSION 3. MEASUREMENT OF AREA 31

Q2. Ramu’s father had a rectangular plot of length 60 ft and breadth 50 ft. He built a house occupying length of 40 ft of the plot and breadth 40 ft, and in the remaining area he planned a garden. Can you help Ramu to find the area of his garden? [Refer to TB page 136 Q4] A. Yes, I can help Ramu to find the area of his garden. He can find the area of the full plot and deduct the area of the house that he has decided to build from it. Step 1: Let us find the area of the rectangular plot. Area of rectangle = Length x Breadth Length of plot = 60 ft, its breadth = 50 ft Area of plot = 60 x 50 square ft = 3000 square ft Step 2: Let us find the area occupied by the house. It has the shape of a square. Area of square = side x side Length of side of square = 40 ft Area occupied by the house = 40 x 40 square feet = 1600 square feet Step 3: Area of the garden = Area of the total plot–Area occupied by the house = 3000 square feet -1600 square feet = 1400 square feet Therefore, area of the garden is 1400 sq ft. Q3. For measuring long distances, we can use as a unit. [Refer to TB page 136 Q7] A. kilometer Q4. How will you measure the area of your palm using graph paper? Explain [Refer to TB page 136 Q11] A. To measure the area occupied by my palm, I will follow the following steps: (1) I will place my palm on a sheet of graph paper as shown in the figure. SESSION 3. MEASUREMENT OF AREA 32

(2) I will mark the boundary of the palm on the graph paper with a sharp pencil. (3) I will remove my palm and then I will find the outline of my palm on the graph paper. (4) I will count the number of complete squares lying inside the boundary line. (5) I will also count those squares which are half or greater than half and add this number to the number of complete squares. (6) I will neglect those squares, inside the boundary which are less than half. (7) If the total number of square is ‘n’. Then the area of my palm is ‘n’ square centimeters. 3.5 Experimentation and Field Investigation Q1. Try to imagine the area of CD, sim card, mobile phone. Then find out the area of these objects by using a graph paper. Compare the values of your guess with graph paper measurements. Which thing is closely related to your guess? [Refer to TB page 137 Q17] A. Students’ Activity 3.6 Information Skills and Projects Q1. Collect any invitation card with envelope. Find out the difference between the measure- ments of card and cover. Write down the process that you follow. [Refer to TB page 137 Q15] A. 1) The length and breadth of the card and its envelope were measured with a scale. 2) Measurements of the covers: SESSION 3. MEASUREMENT OF AREA 33

Length of the cover = l1 = a cm Breadth of the cover = b1 = x cm 3) Measurements of the card: Length of the card = l2 = b cm Breadth of the card = b2 = y cm 4) The areas of the card and its envelope were calculated using the formula = length x breadth. So, area of cover was found as “ax” cm2 and that of card was calculated as “by” cm2 . And then, the difference was found out by subtracting the two areas. 5) The card suitably fitted in the cover. SESSION 3. MEASUREMENT OF AREA 34

SESSION 4 MEASUREMENT OF VOLUME 4.1 Mind Map 4.2 Terminology i. Volume –The amount of space that a substance or object occupies, or that is en- closed within a container. ii. Measuring cylinder –It is a common piece of laboratory equipment used to measure the volume of a liquid. iii. Litre – It is an SI accepted metric system unit of volume equal to 1 cubic decimetre m3 ), 1,000 cubic centimetres m3 ) or 1/1,000 cubic metre. iv. Millilitre –One thousandth of a litre. 4.3 Key Concepts i. Volume is the quantity of three–dimensional space enclosed by a closed surface, for example, the space that a substance (solid, liquid, gas, or plasma) or shape occupies or contains. SESSION 4. MEASUREMENT OF VOLUME 35

ii. Basic unit of volume is a cube. iii. The volume of solids is expressed in cubic measurements, such as cubic centimetre or cubic meter. iv. Liquids are fairly simple to measure, remembering that 1000 cubic centimetres equals 1 litre and 1000 litres equals 1 cubic metre. The volume of a liquid is expressed in milli litres (ml) or litres (I). 1cm3 = 1 ml v. The volume of irregular objects can be determined by using a measuring cylinder taking rise in volume of water as reference. 4.4 Conceptual Understanding Q1. Match the following. [Refer to TB page 136 Q5] SESSION 4. MEASUREMENT OF VOLUME 36

A. AB a A litre ii 1000ml b A meter iii 100cm c A kilometer iv 1000m d A centimeter v 10 mm e 1 hectare i 1000m2 Q2. Millilitre is a unit for measuring . [Refer to TB page 136 Q6] A. volume Q3. Identify incorrect statements among the following and rewrite them with necessary cor- rections: [Refer to TB page 136 Q9] a) One square meter is equal to 100 square centimeters. b) The appropriate unit for reporting the volume of a cylindrical rod is cm2 . c) The appropriate instrument to measure the thickness of a 25 paisa coin is a tailor’s tape. d) A measuring cylinder can directly measure the volume of solids. A. a) The statement is incorrect as 1 meter = 100 centimeters. Therefore, 1 m x 1 m = 1 sq m = 100 cm x 100 cm = 10,000 sq cm. Therefore, the correct statement is one square meter is equal to 10,000 square centimeters. b) The statement is incorrect. The appropriate unit for reporting the volume of a cylindrical rod is cm3 . SESSION 4. MEASUREMENT OF VOLUME 37

c) The statement is incorrect. The appropriate instrument to measure the thickness of a 25 paise coin is scale. d) The statement is partially correct, as a measuring cylinder can directly measure the volume of solids which will sink in water. 4.5 Experimentation and Field Investigation Q1. Measure the volume of “Kalkhanda” (sugar crystal) and piece of “Patika” (alum). Record your measurements in the given table. Ask your friends to measure volumes of the same pieces of Kalkhanda and Patika and record the values. [Refer to TB page 136 Q12] S. Name of the Volume of Volume of No. student Kalkhanda Patika 1 2 3 4 • Are all the values of volumes of Kalkhanda equal? • Are all the values of volumes of Patika equal? • If not, state the possible reasons. A. Students’ Activity Q2. What method will you adopt to measure the volume of a banana? Explain. [Refer to TB page 136 Q8] A. Note : A banana floats on water. So, we must use a heavy object such as a stone to make the banana sink. SESSION 4. MEASUREMENT OF VOLUME 38

Procedure: (1) Take a measuring cylinder. (2) Fill half of it with water and keep it on a table. (3) Take a stone, tie it at one end of a fine piece of thread and immerse it in the measuring cylinder with water. (4) Hold the other end of thread with your left hand and note the level of water in the measuring cylinder without parallax error (say ‘x’ ml). (5) Now take the stone out of water. (6) Tie the banana and the stone together with the help of the thread, so that the banana also sinks along with the stone. (7) See that there are no air bubbles in water. Note the level of water in the measuring cylinder (say ‘y’ ml). (8) The difference between two readings, that is (y - x) ml gives the volume of banana. —— CCE Based Practice Questions —— AS1-Conceptual Understanding Very Short Answer Type Questions 1. Answer the following questions in one sentence. [Refer to Session 13.2 ] (i) Define a gram. 2. Fill in the blanks. [Refer to Session 13.2 ] . (ii) A foot is divided into 3. Answer the following questions in one sentence. [Refer to Session 13.3 ] CHAPTER 13. LEARNING HOW TO MEASURE 39

(iii) Define area. (iv) What is the standard unit to measure the area of a surface? 4. Fill in the blanks. [Refer to Session 13.3 ] (v) The Mughal measurement system measured land in terms of and . (vi) We need to measure the of an object to decide whether it is bigger or smaller. (vii) and are units of measurement. 5. Answer the following questions in one sentence. [Refer to Session 13.4 ] (viii) Define volume. (ix) What is the relationship between volume of liquids and volume of solids? CHAPTER 13. LEARNING HOW TO MEASURE 40

6. Fill in the blanks. [Refer to Session 13.4 ] (x) is used to measure the volumes of liquids. (xi) The volume of liquids is expressed in or . (xii) is a standard unit of measurement of volume of solids. Short Answer Type Questions 7. Answer the following questions in 3-4 sentences. (i) [(Session 13.1)] What is the standard unit of length? Write down other smaller units of length? (ii) [(Session 13.1)] What is a foot distance? 41 CHAPTER 13. LEARNING HOW TO MEASURE

(iii) [(Session 13.1)] Write about the larger unit of length. (iv) [(Session 13.1)] What are the errors that are commonly made while using a metre scale? CHAPTER 13. LEARNING HOW TO MEASURE 42

Long Answer Type Questions 8. Answer the following questions in 6-8 sentences. (i) [(Session 13.3)] Given below are the symbols of the units of length and area.Write down their full forms. i. ft ii. mm2 iii. cm iv. m2 v. ft2 9. Answer the following questions in 6-8 sentences. (i) [(Session 13.1)] Name the place where the standard measurement of scale was pre- pared for the first time. Write a few points about it. CHAPTER 13. LEARNING HOW TO MEASURE 43

(ii) [(Session 13.1)] How was the metre scale discovered? 10. Answer the following questions in 6-8 sentences. 44 (i) [(Session 13.4)] What is a measuring cylinder? CHAPTER 13. LEARNING HOW TO MEASURE

AS2-Asking questions and making hypothesis Short Answer Type Questions 11. Answer the following questions in 3-4 sentences. (i) [(Session 13.2)] How can one prevent the occurence of any error while measuring objects using a meter scale. (ii) [(Session 13.2)] How can we be accurate in our measurement? CHAPTER 13. LEARNING HOW TO MEASURE 45

AS3-Experimentation and field investigation Short Answer Type Questions 12. Answer the following questions in 3-4 sentences. (i) [(Session 13.2)] How would you measure the thickness of a single five rupee coin when 10 such coins are placed one upon the other? AS4-Information skills and projects Long Answer Type Questions 13. Answer the following questions in 6-8 sentences. (i) [(Session 13.4)] Fill the empty spaces in the table given below with appropriate units of measurement and the symbols: CHAPTER 13. LEARNING HOW TO MEASURE 46

Sl.no. Geometry Units of Symbol 1. Length measurement 2. Area 3. Volume 4. Distance AS5-Communication through drawing and model making Long Answer Type Questions 14. Answer the following questions in 6-8 sentences. (i) [(Session 13.4)] What does the following diagram indicate? Explain the procedure. CHAPTER 13. LEARNING HOW TO MEASURE 47

AS6-Appreciation and aesthetic sense, Values Long Answer Type Questions 15. Answer the following questions in 6-8 sentences. (i) [(Session 13.2)] How do you appreciate the introduction of Platinum–Iridium metre scale in France for measuring length? CHAPTER 13. LEARNING HOW TO MEASURE 48