181910053-Maple-G3-Textbook-Integrated-Term 2_Text

Application We have learnt how to read the time. Now let us draw hands on the clocks when the time is given. Example 9: Draw the hands of a clock to show the given time. a) 1:15 b) 6:15 c) 7:30 d) 9:45 Solution: To draw the hands of a clock, first note the minutes. If the minutes are between 1 and 30, draw the hour hand between the given hour and the next. But care should be taken to draw it closer to the given hour. If the minutes are between 30 and 60, draw the hour hand closer to the next hour. Then, draw the minute hand on the number that shows the given minutes. a) b) c) d) Example 10: Draw the hands of a clock to show the given time. a) Quarter to 7 b) Half past 4 Solution: a) b) Time 23 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 51 2/15/2018 10:16:28 AM

Higher Order Thinking Skills (H.O.T.S.) We have learnt to read and show time, exact to minutes and hours. Let us now learn to find the length of time between two given times. Example 11: The clocks given show the start time and the end time of the Maths class. How long was the class? Solution: The start time is 10:00 and the end time is 10:45. The difference in the given times = 10:45 – 10:00 = 45 minutes Therefore, the length of the Maths class was 45 minutes. Example 12: Sanjay spends an hour between 4:30 and 5:30 for different activities. The start time for each activity is as shown. Train My Brain playing drinking milk homework TV on TV off Read the clocks and answer the following questions. a) When did Sanjay begin drinking milk? b) For how long did he play? c) For how long did he watch TV? d) When did he switch off the TV? Solution: From the given figures, a) Sanjay began drinking milk at 4:45. 24 2/15/2018 10:16:29 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 52

b) Sanjay began playing at 4:30 and ended at 4:45. So, he played for a quarter hour (15 minutes) as 4:45 – 4:30 = 15 minutes. c) The time for which he watched TV was 5:30 – 5:20 = 10 minutes. d) Sanjay switched off the TV at 5:30. The time between two given times is called the length of time. It is also called time duration or time interval. It is given by the difference of end time and start time. Drill Time Concept 7.1: Read a Calendar 1) Observe the calendar and answer the following questions. a) H ow many weekends and weekdays are 2019 JANUARY there in the month shown in the calendar? SUN MON TUES WED THU FRI SAT (Consider Saturday and Sunday as weekend 12345 days.) 6 7 8 9 10 11 12 b) Write the day and date before two days of 13 14 15 16 17 18 19 20 21 22 23 24 25 26 the fourth Saturday of January. 27 28 29 30 31 c) On which day does the month end? 2) Word Problems a) Raju bought a new dress on 1st September. 2018 SEPTEMBER He bought another new dress 10 days after SUN MON TUES WED THU FRI SAT first day of the same month. On which date did he buy the other dress? 1 2 3 45678 9 10 11 12 13 14 15 b) S hane’s birthday was on 2nd September. 16 17 18 19 20 21 22 What is the date, if he celebrated it on the 23 24 25 26 27 28 29 same day of the third week. 30 c) Arif solved problems from one chapter of his book on 9th of September. He solved problems from the next chapter 5 days later. On which day did he solve problems from the next chapter? Concept 7.2: Read Time Correct to the Hour 3) Draw the hands of the clock to show the given time. a) Half past 2 b) 4:15 c) Quarter to 12 d) 4:25 e) 6:20 Time 25 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 53 2/15/2018 10:16:29 AM

4) What is the time shown on each of these clocks? 5) Word problems a) On which number is the minute hand if the time is as given? A) 25 minutes B) 45 minutes C) 20 minutes D) 50 minutes b) The start time of Ram’s activities are shown in these figures. wake up brush have bath Wear uniform study breakfast From the figures, answer the following questions. A) When did Ram wake up? B) How much time did Ram spend for wearing his school uniform? C) When did Ram start studying? D) At what time did Ram had his breakfast? 26 2/15/2018 10:16:29 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 54

Chapter Division 8 Let Us Learn About • equal grouping and sharing. • repeated subtraction and division facts. • dividing 2-digit number by 1-digit number. • checking the correctness of division. Concept 8.1: Division as Equal Grouping Think Farida and her brother Piyush got a chocolate bar with 14 pieces for Christmas. Piyush divided it and gave Farida 6 pieces. Do you think Farida got an equal share? How can we find out? Recall In the previous chapter, we have learnt multiplication. Multiplication is finding the total number of objects that have been grouped equally. Let us use this to distribute objects equally in groups. Consider 12 bars of chocolate. The different ways in which they can be distributed are as follows. 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 55 27 2/15/2018 10:16:29 AM

Distributing in 1 group: 1 × 12 = 12 Distributing in 2 groups: 2 × 6 = 12 Distributing in 3 groups: 3 × 4 = 12 Distributing in 4 groups: 4 × 3 = 12 Distributing in 6 groups: 6 × 2 = 12 Distributing in 12 groups: 12 × 1 = 12 Distributing a given number of objects into equal groups is called division. We can understand division better by using equal sharing and equal grouping. & Remembering and Understanding Equal sharing means having equal number of objects or things in a group. We use division to find the number of things in a group and the number of groups. 28 2/15/2018 10:16:29 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 56

Suppose 9 balloons are to be shared 1st round: 1 balloon is taken by each equally among 3 friends. Let us use friend. repeated subtraction to distribute the balloons. 9 – 3 = 6. So, 6 balloons remain. 2nd round: From the remaining 6 balloons, 3rd round: From the remaining 3 balloons, 1 more balloon is taken by each friend. 1 more balloon is taken by each friend. Now, each friend has 2 balloons. Now, each of them has 3 balloons. 6 – 3 = 3. So, 3 balloons remain. 3 – 3 = 0. So, 0 balloons remain. Each friend gets 3 balloons. We can write it as 9 divided by 3 equals 3. 9 divided by 3 equals 3 is written as ↓ ↓ ↓ Total Number of Number of number of objects in each groups objects group Quotient Dividend Divisor Division 29 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 57 2/15/2018 10:16:29 AM

In a division, the number that is divided is called the dividend. The number that divides is called the divisor. The answer in division is called the quotient. The number (part of the dividend) that remains is called the remainder. The symbol for ‘is divided by’ is ÷. 9 ÷ 3 = 3 is called a division fact. In this, 9 is the dividend, 3 is the divisor and 3 is the quotient. Note: Representing the dividend, divisor and quotient using the symbols ÷ and = is called a division fact. We use multiplication tables to find the quotient in a division. We find the factor which when multiplied by the divisor gives the dividend. Let us understand this through a few examples. Example 1: 18 pens are to be shared equally by 3 children. How many pens does each of them get? Solution: Total number of pens = 18 Number of children = 3 Number of pens each child gets = 18 ÷ 3 = 6 (since 6 × 3 = 18) Therefore, each child gets 6 pens. Example 2: 10 flowers are put in some vases. If each vase has 2 flowers, how many vases are used? Solution: Number of flowers = 10 Number of flowers in each vase = 2 Number of vases used = 10 ÷ 2 = 5 (since 2 × 5 = 10) Therefore, 5 vases are used to put 10 flowers. We get two division facts from a multiplication fact. The divisor and the quotient are the factors of the dividend. 30 2/15/2018 10:16:29 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 58

Observe the following table: Dividend ÷ Divisor = Quotient Multiplicand × Multiplier = Product 6 × 3 = 18 18 ÷ 6 = 3 ↓↓ ↓ ↓↓ ↓ Divisor Quotient Dividend Product Factor Factor (Multiplicand) (Multiplier) From the multiplication fact 6 × 3 = 18, we can write two division facts: a) 18 ÷ 3 = 6 and b) 18 ÷ 6 = 3 Multiplication and division are reverse operations. Let us now understand this through an activity. We can show a multiplication fact on the number line. For example, 3 × 5 = 15 means 5 times 3 is 15. To show 5 times 3 on the number line, we take steps of 3 for 5 times. We go forward from 0 to 15. Similarly, we can show the division fact 15 ÷ 3 = 5 on the number line. To show 15 divided by 3 on the number line, we take steps of 3 for 5 times. We go backward from 15 to 0 as shown. Division 31 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 59 2/15/2018 10:16:29 AM

Application Equal sharing and equal grouping are used in some real-life situations. Consider the following situations. Example 3: 25 buttons are to be stitched on 5 shirts. If each shirt has the same number of buttons, how many buttons are there on each shirt? Solution: Total number of buttons = 25 Number of shirts = 5 The division fact for 25 buttons distributed among 5 shirts = 25 ÷ 5 = 5 Therefore, each shirt has 5 buttons on it. Example 4: 24 marbles are to be divided among 4 friends. How many marbles will each friend get? Solution: Total number of marbles = 24 Number of friends = 4 Number of marbles each friend will get = 24 ÷ 4 = 6 Therefore, each friend will get 6 marbles. Higher Order Thinking Skills (H.O.T.S.) Division is used in many situations in our day-to-day lives. Let us see some examples. Example 5: Aman spends 14 hours a week for tennis practice. He spends 21 hours a week for doing homework and 48 hours a week at school. How much time does he spend in a day for these activities? (Hint: 1 week = 7 days. The school works for 6 days a week.) Solution: Time spent for tennis practice per day = 14 hours ÷ 7 = 2 hours Time spent for doing homework per day = 21 hours ÷ 7 = 3 hours Time spent at school per day = 48 hours ÷ 6 = 8 hours (School works for 6 days a week) Thus, the total time spent by Aman in a day for all the activities = (2 + 3 + 8) hours = 13 hours (except Sunday) 32 2/15/2018 10:16:29 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 60

Example 6: Deepa shares 15 lollipops among her 5 friends. Instead, if she shares the lollipops among only 3 of them, how many more lollipops does each of them get? Solution: Number of lollipops = 15 If Deepa shares the lollipops among her five friends, the number of lollipops each of them would get = 15 ÷ 5 = 3 If Deepa shares the lollipops among only three of them, the number of lollipops each of them gets = 15 ÷ 3 = 5 Difference in the number of lollipops = 5 – 3 = 2 Therefore, her friends would get 2 more lollipops. Concept 8.2: Divide 2-digit and 3-digit Numbers by 1-digit Numbers Think Farida has 732 stickers. She wants to distribute them equally among her three friends. How will she distribute? Recall In the previous section, we have learnt that division is related to multiplication. For every division fact, we can write two multiplication facts. For example, the two multiplication facts of 35 ÷ 7 = 5 are: a) 7 × 5 = 35 and b) 5 × 7 = 35. Let us answer these to recall the concept of division. a) The number which divides a given number is called _________________. b) The answer we get when we divide a number by another is called ______________________. c) The division facts for the multiplication fact 2 × 4 = 8 are ________________ and __________________. Division 33 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 61 2/15/2018 10:16:29 AM

& Remembering and Understanding We can make equal shares or groups and divide with the help of vertical arrangement. A number divided by the same number is always 1. Let us see some examples. Dividing a 2-digit number by a 1-digit number (1-digit quotient) Example 7: Solve: 45 ÷ 5 Solution: Follow these steps to divide a 2-digit number by a 1-digit number. Steps Solved Solve these Step 1: Write the dividend and 5)45 Dividend = _____ Divisor = ______ )divisor as shown: Divisor Dividend Quotient = ____ Remainder = _____ Step 2: Find the multiplication fact 45 = 5 × 9 8) 56 which has the dividend and divisor. - Step 3: Write the other factor as the 9 quotient. Write the product of the factors below the dividend. 5)45 − 45 Step 4: Subtract the product 9 4) 36 Dividend = _____ from the dividend and write the Divisor = ______ difference below the product. 5)45 - Quotient = ____ This difference is called the Remainder = _____ remainder. − 45 00 45 = Dividend 5 = Divisor 9 = Quotient 0 = Remainder Note: If the remainder is zero, the divisor is said to divide the dividend exactly. Checking for correctness of division: The multiplication fact of the division is used to check its correctness. Step 1: Compare the remainder and divisor. The remainder must always be less than the divisor. 34 2/15/2018 10:16:29 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 62

Step 2: Check if (Quotient × Divisor) + Remainder = Dividend Let us now check if our division in example 7 is correct or not. Step 1: Remainder < Divisor 0 < 5 (True) Step 2: Quotient × Divisor 9×5 Step 3: (Quotient × Divisor) + Remainder = Dividend 45 + 0 = 45 = Dividend Note: The division is incorrect if: a) Remainder > or = divisor b) (Quotient × Divisor) + Remainder ≠ Dividend 2-digit quotient In the examples we have seen so far, the quotients are 1-digit numbers. In some divisions, the quotients may be 2-digit numbers. Let us see some examples. Example 8: Solve: 57 ÷ 3 Solution: Follow these steps to divide a 2-digit number by a 1-digit number. Steps Solved Solve these Step 1: Check if the tens digit of the dividend is greater than the divisor. 5>3 5) 60 Step 2: Divide the tens and write the quotient. 1 − Write the product of quotient and divisor, below the tens digit of the dividend. 3)57 − Step 3: Subtract and write the difference −3 Step 4: Check if difference < divisor is true. 1 Dividend = _____ Divisor = ______ 3)57 Quotient = ____ Remainder = ___ −3 2 2 < 3 (True) Division 35 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 63 2/15/2018 10:16:29 AM

Steps Solved Solve these Step 5: Bring down the ones digit of the 1 3) 42 dividend and write it beside the remainder. 3)57 − − − 3↓ 27 Step 6: Find the largest number in the 3 × 8 = 24 19 multiplication table of the divisor that can be subtracted from the 2-digit number in )3 × 9 = 27 3 57 the previous step. 3 × 10 = 30 24 < 27 < 30. − 3↓ So, 27 is the 27 required number. Step 7: Write the factor of required number, 19 Dividend = _____ other than the divisor, as the quotient. Write Divisor = ______ the product of the divisor and the quotient 3)57 Quotient = ____ below the 2-digit number. Subtract and Remainder = ___ write the difference. − 3↓ 27 Step 8: Check if remainder < divisor is true. Stop the division. − 27 00 0 < 3 (True) (If this is false, the division is incorrect.) RQeumotaieinndte=Trr1=a90in My Brain Step 9: Write the quotient and the remainder. Step 10: Check if (Divisor × Quotient) + 3 × 19 + 0 = 57 Remainder = Dividend is true. 57 + 0 = 57 57 = 57 (True) (If this is false, the division is incorrect.) Divide 3-digit numbers by 1-digit numbers (2-digit quotient) Dividing a 3-digit number by a 1-digit number is similar to dividing a 2-digit number by a 1-digit number. Let us understand this through a few examples. Example 9: Solve: a) 265 ÷ 5 Solution: Follow these steps to divide a 3-digit number by a 1-digit number. 36 2/15/2018 10:16:29 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 64

Steps Solved Solve these Step 1: Check if the hundreds digit of 4) 244 the dividend is greater than the divisor. 5)265 − If it is not, consider the tens digit too. 2 is not greater than 5. So, consider 26. Step 2: Find the largest number that 5 − can be subtracted from the 2-digit number of the dividend. Write the 5)265 Dividend = _____ quotient. Divisor = ______ − 25 Quotient = ____ Remainder = ___ Write the product of the quotient and 5 × 4 = 20 the divisor below the dividend. 5 × 5 = 25 9) 378 5 × 6 = 30 Step 3: Subtract and write the − difference. 25 < 26 − 5 5)265 − 25 1 Step 4: Check if difference < divisor 1 < 5 (True) is true. (If it is false, the division is incorrect.) Step 5: Bring down the ones digit 5 of the dividend. Write it beside the remainder. 5)265 Step 6: Find the largest number in the − 25↓ multiplication table of the divisor that 15 can be subtracted from the 2-digit number in the previous step. 5 5)265 − 25↓ 15 5 × 2 = 10 5 × 3 = 15 5 × 4 = 20 15 is the required number. Division 37 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 65 2/15/2018 10:16:29 AM

Steps Solved Solve these Step 7: Write the factor of required 53 number, other than the divisor, as Dividend = _____ quotient. Write the product of divisor 5)265 Divisor = ______ and quotient below the 2-digit Quotient = ____ number. Then, subtract them. − 25↓ Remainder = ___ 15 Step 8: Check if remainder < divisor is true. Stop the division. (If this is false, − 15 the division is incorrect.) 00 0 < 5 (True) Step 9: Write the quotient and Quotient = 53 remainder. Remainder = 0 Step 10: Check if (Divisor × Quotient) + 5 × 53 + 0 = 265 Remainder = Dividend is true. (If this is 265 + 0 = 265 false, the division is incorrect.) 265 = 265 (True) 3-digit quotient Example 10: Solve: 784 by 7 Solution: Follow these steps to divide a 3-digit number by a 1-digit number. Steps Solved Solve these Step 1: Check if the hundreds digit of the dividend is greater than or equal to the 7)784 8) 984 divisor. Step 2: Divide the hundreds and write the 7=7 − quotient in the hundreds place. 1 − Write the product of the quotient and the divisor under the hundreds place of the 7)784 − dividend. −7 38 2/15/2018 10:16:29 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 66

Steps Solved Solve these Step 3: Subtract and write the difference. Dividend = _____ 1 Divisor = ______ Quotient = ____ 7)784 Remainder = ___ −7 5) 965 0 − Step 4: Check if difference < divisor is true. 0 < 7 (True) − Step 5: Bring down the next digit of the 1 − dividend. Check if it is greater than or equal to the divisor. 7)7 84 Dividend = _____ Divisor = ______ − 7↓ Quotient = ____ 08 Remainder = ___ 8>7 Step 6: Find the largest number in the 11 multiplication table of the divisor that can be subtracted from the 2-digit number in 7)784 the previous step. − 7↓ Write the factor other than the divisor as 08 quotient. −7 Write the product of the quotient and the divisor below it. 7×1=7<8 The required number is 7. Step 7: Subtract and write the difference. 11 Bring down the next digit (ones digit) of the dividend. 7)784 Check if the dividend is greater than or − 7↓ equal to the divisor. 08 −7 14 14 > 7 Division 39 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 67 2/15/2018 10:16:29 AM

Steps Solved Solve these Step 8: Find the largest number in the multiplication table of the divisor that can 112 2) 246 be subtracted from the 2-digit number in the previous step. 7)784 − − Write the factor other than the divisor as − 7↓ − the quotient. 08 Dividend = _____ Write the product of the quotient and the −7 Divisor = ______ divisor below it. 14 Quotient = ____ Remainder = ___ − 14 Step 9: Subtract and write the difference. 7 × 2 = 14 Check if it is less than the divisor. Stop the The required division. number is 14. Step 10: Write the quotient and the 112 remainder. 7)784 − 7↓ 08 −7 14 − 14 00 Quotient = 112 Remainder = 0 Step 11: Check if (Divisor × Quotient) + 7 × 112 + 0 = 784 Remainder = Dividend is true. (If it is false, 784 + 0 = 784 the division is incorrect.) 784 = 784 (True) 40 2/15/2018 10:16:29 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 68

Application Division of 2-digit numbers and 3-digit numbers is used in many real-life situations. Let us consider a few examples. Example 11: A school has 634 students, who are equally grouped into 4 houses. How many students are there in a house? Are there any students who are not grouped into a house? Solution: Number of students = 634 158 Number of houses = 4 Number of students in a house = 634 ÷ 4 4)634 − 4↓ 23 Number of students in each house = 158 − 20 The remainder in the division is 2. 34 Therefore, 2 students are not grouped into any house. − 32 02 Example 12: A football game had 99 spectators. If each row has only 9 seats, how many rows would the spectators occupy? Solution: Number of spectators = 99 11 Number of seats in each row = 9 Number of rows occupied by the spectators = 99 ÷ 9 = 11 9) 99 Therefore, 11 rows were occupied by the spectators. − 9↓ 09 −9 0 Higher Order Thinking Skills (H.O.T.S.) In all the division sums we have seen so far, we did not have a 0 (zero) in dividend or quotient. When a dividend has a zero, we place a 0 in the quotient in the corresponding place. Then, get the next digit of the dividend down and continue the division. Let us now understand division of numbers that have a 0 (zero) in dividend or quotient, through these examples. Example 13: Solve: 505 ÷ 5 Solution: Follow these steps for division of numbers having 0 in dividend. Division 41 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 69 2/15/2018 10:16:29 AM

Solved Solve this 101 4) 804 5)505 − − 5↓ − 00 − − 00 05 − 05 00 Drill Time Concept 8.1: Division as Equal Grouping 1) Divide the number in equal groups. a) 16 in 4 equal groups b) 18 in 9 equal groups c) 20 in 5 equal groups d) 32 in 8 equal groups e) 10 in 2 equal groups 2) Word Problems a) 2 6 students are to be divided into 2 groups. How many students will be there in each group? b) 14 pencils must be distributed among 7 children. How many pencils will each student receive? Concept 8.2: Divide 2-digit and 3-digit Numbers by 1-digit Numbers 3) Divide 2-digit numbers by 1-digit numbers (1-digit quotient). a) 12 ÷ 2 b) 24 ÷ 6 c) 36 ÷ 6 d) 40 ÷ 8 e) 10 ÷ 5 4) Divide 2-digit numbers by 1-digit numbers (2-digit quotient). a) 12 ÷ 1 b) 99 ÷ 3 c) 48 ÷ 2 d) 65 ÷ 5 e) 52 ÷ 4 42 2/15/2018 10:16:29 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 70

5) Divide 3-digit numbers by 1-digit numbers (2-digit quotient). a) 123 ÷ 3 b) 102 ÷ 2 c) 497 ÷ 7 d) 111 ÷ 3 e) 256 ÷ 4 6) Divide 3-digit numbers by 1-digit numbers (3-digit quotient). a) 456 ÷ 2 b) 112 ÷ 1 c) 306 ÷ 3 d) 448 ÷ 4 e) 555 ÷ 5 7) Word Problems a) 2 60 chocolates have to be equally distributed among 4 students. How many chocolates will each student receive? b) T here are 24 people in a bus. Each row in the bus can seat 2 people. How many rows in the bus are occupied? Division 43 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 71 2/15/2018 10:16:29 AM

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EVS-I (SCIENCE) TERM 2 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 73 2/15/2018 10:16:29 AM

Contents 3Class 7 Sources of Light������������������������������������������������������������������������������������������������������������ 1 8 Composition of Air������������������������������������������������������������������������������������������������������� 5 9 Stems and Leaves�������������������������������������������������������������������������������������������������������� 8 1 0 Uses of Animals���������������������������������������������������������������������������������������������������������� 13 Inside the Lab – B�������������������������������������������������������������������������������������������������������������� 19 Activity B1: My Lava Lamp Activity B2: Leaves Leaves Everywhere! 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 74 2/15/2018 10:16:29 AM

Lesson Sources of Light 7 Let Us Learn About R natural and artificial sources of light. U discovery of fire as a source of light. A electricity as a source of light. H light as heat. Think Nowadays, we see electric bulbs everywhere. What did your grandparents use to light up their homes when they were young? Remembering Our eyes help us to see the things around us. But why are we unable to see in the dark? This is because our eyes can help us to see things only in the presence of light. Where do we get light from? We get light from two different sources: 1) natural sources    2) artificial sources or man-made sources 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 75 1 2/15/2018 10:16:30 AM

Natural sources: These sources include heavenly bodies like the Sun and the stars. the stars the Sun Artificial sources: The artificial sources of light are made by human beings. They include electric bulbs, kerosene lamps, oil lamps, candles and so on. electric bulb kerosene lamp oil lamp candle Understanding In ancient times, there were no artificial flint stones firewood sources of light. Human beings could only hunt and gather food during the day time. artificial light sources then and now Then, humans discovered fire by rubbing flint stones. This helped them to get light even after sunset. They could also guard their caves from dangerous animals with the help of fire. Earlier, humans would burn firewood for light. Time went on. Then they started using oil lamps, candles and lanterns like we do today. After the discovery of electricity, humans started using electric lamps as a source of light. 2 2/15/2018 10:16:30 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 76

Application What type of sources of light should we use? We should try to use sunlight, which is the main source of natural light, to the maximum. It is the cheapest source of light. We can use solar panels to capture light and convert solar panels it to electricity. This electricity can be used to light our LED and CFL bulbs homes in the night. Artificial sources of light like electric bulbs need electricity to give out light. This electricity is limited. So, we should use light sources which use less electricity. For example, LED bulbs, tube lights and CFL bulbs. Moreover, we should switch off the lights when not in use. kerosene Some artificial sources of light cause lamp harm to the environment. For example, kerosene lamps give out smoke. We should try to avoid the use of such harmful sources. Amazing Facts Have you seen fireflies? They are insects that give out light from their bodies. Some aquatic animals like jellyfish also give out light. firefly jellyfish 3 Sources of Light 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 77 2/15/2018 10:16:30 AM

Higher Order Thinking Skills (H.O.T.S.) Many light sources also give us heat. We use fire for cooking as it provides heat. We can use sunlight for heating water and cooking food with the help of solar heater and solar cooker. solar water heater solar cooker 4 2/15/2018 10:16:30 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 78

Lesson Composition of Air 8 Let Us Learn About R air as a mixture. U sources of components of air. A air pollution. H t he bad effects of burning firecrackers. Think Arjun woke up early in the morning to go to school. He found that the air was fresh and cool. When he came back from school in the afternoon, he felt the air was not so fresh and cool. Do you know why? Remembering We know that air is all around us. Air is a mixture of different gases. Gases are substances that can move around freely. Gases do not have any shape of their own. They can fill any available space of any shape. Oxygen, carbon dioxide and nitrogen are the main gases present in the air. Air is mostly made up of nitrogen and oxygen. Carbon dioxide and some other gases are present in smaller amounts. Air also contains water vapour, which is the gaseous form of water, and some dust. Clean air does not have any smell or colour. 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 79 5 2/15/2018 10:16:30 AM

Understanding We have learnt that air contains different gases. Let us find out the sources of these gases. We all need air to breathe. All animals breathe in oxygen and carbon give out carbon dioxide. At dioxide the same time, plants take in carbon dioxide from the air to oxygen make their food. They give out oxygen during this process. In this way, the levels of oxygen and carbon dioxide in the sources of oxygen and carbon dioxide in air air are maintained. What will happen to this balance, if we cut trees unnecessarily? We know that water vapour in the air comes from different water bodies. Once the air gets filled with water vapour, it changes into water droplets and falls as rain. Application Sometimes the air gets filled with smoke and dust. The presence of such harmful substances in the air is called air pollution. Substances which make the air dirty (or pollute the air) are called pollutants. Let us find out the sources of these pollutants. When we burn firewood or a kerosene lamp, it gives out firewood kerosene smoke. Smoke from vehicles and factories also pollute the lamp air. Vehicles also blow up dust in the air. Carbon dioxide is useful at very low levels. But when its amount increases above normal levels, it becomes a pollutant. Any colour or bad smell of air shows air pollution. vehicles factory Polluted air is unhealthy. It may damage our lungs and eyes. It makes us feel tired and sick. 6 2/15/2018 10:16:30 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 80

If the air is polluted, we should wear masks. Masks filter the air and allow only clean air to enter our nose. How can we keep the air clean? 1) Plant trees: Plants absorb carbon dioxide and give out child wearing a mask oxygen. They help to maintain the air clean and healthy. So, we feel fresh when we are in a field, garden or a forest. It is, therefore, important to plant trees. 2) Use smoke-free lamps and stoves: We should avoid using cooking stoves and lamps which give out smoke. 3) Stop burning garbage: We should not burn garbage in our neighbourhood. Plastics in the garbage give out harmful gases on burning. 4) Use well-maintained vehicles: Vehicles that are not maintained or are old give out harmful gases. Amazing Facts As we go higher, the level of oxygen in the air decreases. So, the people who climb mountains carry oxygen cylinders with them. Higher Order Thinking Skills (H.O.T.S.) People burst firecrackers (crackers) on festivals and special occasions. Do you think firecrackers are good for the environment? Firecrackers are made up of chemicals which catch fire easily. They make a lot of noise. They also add harmful smoke to the air causing air pollution. People who make firecrackers in factories suffer from skin and lung problems. firecrackers people who make firecrackers It is dangerous to work in places where they are made or stored. Still, at some places, even small children are forced to work in firecracker factories. We should, therefore, stop bursting firecrackers. Composition of Air 7 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 81 2/15/2018 10:16:30 AM

Lesson Stems and Leaves 9 Let Us Learn About R different types of stems and leaves. U functions of stems and leaves. A uses of stems and leaves. H why plants shed leaves. Think Nitin’s teacher showed him four types of leaves. She asked him to find the difference between them. What differences did Nitin find? Remembering You have learnt about various types of plants. You have also learnt that a plant has different parts. Now, let us learn about the stems and leaves of plants in detail. THE STEM stem leaf The stem is usually seen above the ground. It is generally green when young and later becomes woody and dark brown. The stem is different in different types of plants. 8 2/15/2018 10:16:31 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 82

The stem of a big tree is called the trunk. tree trunk stem with stem without Stems may be with branches or without branches branches branches. For example, mango trees have branches but coconut trees have no branches. Stems are usually erect, but in some plants they can be creeping or twisted. For example, pumpkin plants have creeping stems. The stem of the rose plant has thorns on it. creeper stem thorns on a hair on the In some plants, stems are covered with of pumpkin rose stem stem of a tulsi small hair. plant The stem of the bamboo is smooth, while the stem of the mango tree is rough. We have learnt about the different types of stems in plants. Now, let us learn about the different kinds of leaves. THE LEAVES Leaves are important parts of plants, just like the bamboo stems rough stem or bark stems. They are of different size, shape and colour. of a mango tree They are arranged in different ways in different plants. Shapes Arrangement Edges Let us take a look at some leaves. Banana plants have big leaves and tulsi hand plants have small ones. shaped Peepal trees have heart-shaped leaves. spear simple smooth Lotus plants have round ones. shaped Some leaves have toothed edges. heart compound toothed Example: neem shaped Some leaves have a special smell. round Example: tulsi needle compound lobed different types of leaves Stems and Leaves 9 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 83 2/15/2018 10:16:31 AM

Understanding We have learnt about different types of stems and leaves. But, why do plants need stems and leaves? Let us see how stems and leaves are helpful to plants. Functions OF STEMS 1) The stem allows the plant to stand upright and holds up the branches and leaves. It holds the leaves in such a way that they trunk helps the tree can get maximum sunlight. to stand upright 2) The stem carries water and nutrients from the roots to the leaves. It carries food prepared in the leaves to the different parts of the plant. 3) Some stems store food for the plant. Example: sugarcane sugarcane FUNCTIONS OF LEAVES Plants need food to live. Leaves make sunlight oxygen food for the plant. They also help plants to water carbon dioxide breathe. How do leaves make food? To make food, leaves need sunlight, water and carbon dioxide gas. They use the carbon dioxide gas from the air. Water from the roots reach the leaves through the stem. In the presence of sunlight, leaves combine water and carbon dioxide to make food. During this process, they give out oxygen. So, they are called ‘the kitchen of the plant’ or ‘food factories of the plant’. 10 2/15/2018 10:16:31 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 84

Application We have learnt about the functions of stems and leaves. Now, let us see how we use stems and leaves in our day-to-day life. Uses of stems Some stems are used: • as food, for example, potato and onion. The sugarcane stem is used to make juice, sugar and jaggery. • to make furniture as they are hard and strong. Teak and mahogany are a few examples. • to make medicines. Example: tulsi, neem • to make useful things like rubber and jute. The milky juice from the stem of the rubber tree is used to make rubber. The stem of the jute plant is used to make jute. We make ropes and bags using jute. Uses of leaves Some leaves are used: • as food. Leafy vegetables such as spinach and parsley are some examples. Leaves of the tea plant are used to make tea. • as spices in cooking. Example: bay leaves, coriander • to make medicines, for example, the leaves of the tulsi and neem plants. • to cook and serve food. Example: turmeric leaf, banana leaf • as decorations during festivals and special occasions. bay leaves cooking food using a leaf serving food on a leaf Stems and Leaves 11 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 85 2/15/2018 10:16:31 AM

Amazing Facts The green colour of leaves is due to a substance called chlorophyll. Leaves turn brown due to a substance called tannin. Tannin also gives the colour to your tea. Higher Order Thinking Skills (H.O.T.S.) During the winter season, some trees shed all their leaves. Leaves of some trees also change their colour. Do you know why they do so? Try to find out. shedding of leaves leaves changing colours There are some trees where leaves are not in their normal form. For example, cactus plant. The leaves of cactus are reduced to spines. cactus plant with spines 12 2/15/2018 10:16:31 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 86

Lesson Uses of Animals 10 Let Us Learn About r animal products. u trained animals. a people who depend on animals for their livelihood. h kindness towards animals. Think Have you ever wondered where we get woollen clothes from? Or where does the milk that you drink every morning come from? Remembering We find many animals around us. Some of them are very useful. Animals give us food and other things that we can use. Let us see how animals are useful to us: 1) Some animals and birds provide food. Animals like cows, buffaloes and goats give milk. They are called milch animals. We use milk to drink and to prepare milk products/dairy products. Curd, butter, ghee and cheese are some milk products. 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 87 13 2/15/2018 10:16:31 AM

cow buffalo milk and milk products hen Birds like hens and ducks eggs meat give us eggs. The meat of various animals and birds is used as food. Some aquatic (water) animals like fish and prawns are also used as food. 2) We get honey from honeycombs. We use honey in food and as prawns honeycomb honey medicine. fish 3) Animals like sheep and rabbit give us wool. Wool is used to make woollen clothes. They protect us from the cold. sheep wool woollen clothes 4) We get leather from the skin of animals like cows, pigs, goats, sheep, alligators and kangaroos. Bags, purses and belts are made from leather. We get fur from the skin of some animals like minks, foxes and rabbits. Fur is also used to make purses and coats. leather from animal skin bags, purses, shoes, belts animal fur fur coat 14 2/15/2018 10:16:31 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 88

5) Lac insects give us lac. It is used to make dyes. It is also used to make bangles. lac insect lac lac bangles 6) Silkworms give us silk threads. They are used to make silk cloth. silkworm silk thread silk cloth 7) Oyster, a kind of sea animal, gives us pearls.    oyster pearls 8) Animal waste is used to produce cooking gas. In village areas, dried cow dung is used instead of firewood. dried cow dung used as firewood Uses of Animals 15 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 89 2/15/2018 10:16:31 AM

Understanding We have learnt about the useful things we get from animals. Now, let us discuss about some other uses of animals. Some animals are trained to help humans in their work and transport. 1) Animals like horses, elephants and camels are trained to carry people and goods. Horses and bullocks pull carts. There are some places where modern modes of transport do not work. In such places animals like mules and camels help us in transport. Mules are trained to climb hills carrying goods. horse cart animals used for riding mules carrying goods camels in the desert Camels can move across the desert sand easily. They are called the ship of the desert. 2) Dogs are trained to help us in many ways. Police train dogs to catch thieves or to smell bombs. Dogs can be trained to guard our houses. They can be trained to help people with special needs like the blind people. police dog guard dog guide dog 16 2/15/2018 10:16:31 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 90

3) Some animals are trained to help us in farm work. bullocks used in farm 4) In a circus, wild animals like elephants, monkeys and parrots are trained to do tricks. Sea animals like dolphins are also trained to perform in front of people. Nowadays, to stop animal cruelty, a circus is not allowed in many countries. monkeys entertaining people talking parrot trained dolphin Application We have seen various uses of animals in the form of products, transport and safety. Many people depend on animals for their work. Let us see how. People like milkmen and fishermen depend on animals for their livelihood. Some people rear goats and sheep for their milk and meat. To rear is to take care of animals until they are fully grown. People rear birds like hens and ducks for their meat and eggs. It is called poultry farming. fish farming goat farming poultry farming Snake charmers perform tricks using snakes to earn money. Some people train monkeys and use them to perform tricks. Have you seen such animal charmers? How do you feel when you look at those animals? Human beings used to hunt wild animals for food since ancient times. We came to know about it through rock paintings. Have you seen any such ancient rock paintings? Uses of Animals 17 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 91 2/15/2018 10:16:31 AM

snake charmer monkey charmer ancient rock painting Amazing Facts An Indian sheep can yield about 5 kg wool per year. This roughly means that every year the wool got from each Indian sheep can be used to make fourteen sweaters. Indian sheep Higher Order Thinking Skills (H.O.T.S.) So far, we have seen that animals are very useful to us. In our country, people worship animals like cows, elephants, snakes and so on. This is to respect their usefulness to us. We should treat all animals with kindness. We should not hurt them. We should take care of the animals around us. Here are some ways to take care of animals: 1) We should give enough food and water to the animals we rear. We should keep them in clean and airy shelters. 2) We should not put heavy loads on the animals used for transport. We should not beat them. 3) We should not hurt them while training them. 4) We should keep them healthy and get an animal doctor (veterinarian) to check them regularly. These days, killing wild animals for their skin, fur, nails, horns or tusks is not allowed as per the law. Keeping them in a cage is also not allowed. 18 2/15/2018 10:16:31 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 92

Inside the Lab – B Make sure you do these activities only with the help of a teacher or an adult. Activity B1: My Lava Lamp A lava lamp is a tube-shaped light. It has a coloured, oily liquid inside it that flows up and down. Let us try to build a lava lamp. It is very easy and a lot of fun! You will need: a cup of water, a clear plastic bottle, vegetable oil, food colouring, ENO fruit salt (or other antacid tablets) and glitter (optional). You need to: 1) pour water into the plastic bottle until it is around one-quarter full. lava lamps 2) pour the vegetable oil until the bottle is nearly full. 3) wait until the oil and water have separated from each other. 4) add around twelve drops of food colouring to the bottle. You can add glitter too. 5) watch as the food colouring goes through the oil and mixes with the water. 6) add some ENO into the bottle; things should start getting a little crazy, just like a real lava lamp! 7) add some more ENO when the bubbling stops and enjoy the changes. 8) shine a torch behind or underneath your lava lamp to see it glow. How do you get the movement inside the lava lamp? When we add ENO, it mixes with water to form carbon dioxide gas. This gas causes colour bursts and movements inside the lava lamp. [Note: Oral intake of ENO or antacid tablets should be strictly avoided during the activity.] 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 93 19 2/15/2018 10:16:31 AM

Activity B2: Leaves Leaves Everywhere! We see many different types of leaves Shapes Arrangement Edges around us. They differ in colour, shape, smooth size, arrangement and so on. hand toothed shaped Go on a nature walk to a local park or a garden in your school premises to see spear simple the different types of leaves. shaped You will need: heart shaped a paper bag, a pencil, an eraser and a set of colour pencils. compound round You need to: needle 1) take a paper bag and collect as compound lobed many types of leaves as you can. different types of leaves 2) make sure that you pick 3 – 4 leaves of the same plant. 3) group all the leaves by shapes, arrangements and edges (as shown in the picture). 4) trace the shapes of the leaves in your notebook. 5) colour the leaves with your favourite colours. Show your colourful leaf journal to your friends. trace and paint leaves 20 2/15/2018 10:16:31 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 94

EVS - II (SOCIAL STUDIES) TERM - 2 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 95 TERM 1 2/15/2018 10:16:31 AM

Contents 3Class 4 United We Stand - I 4.1 L anguages, Food and Clothing����������������������������������������������������������������������������� 1 5 United We Stand - II 5.1 Communities and Festivals������������������������������������������������������������������������������������� 9 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 96 2/15/2018 10:16:32 AM

Lesson United We Stand - I 4 Let Us Learn About 4.1 R culture, languages, clothing and food habits of different people of India. U diversity and how natural regions and climate affect culture. A ‘unity in diversity’ in India. h comparison of the cultures of different states. Concept 4.1: Languages, Food and Clothing Think Rashi is having lunch with the Irani family. They are discussing the similarities and the differences between the Irani and Jain families. Meher: Rashi, would you like to taste this patrani machchi? It is a famous Parsi fish dish. Rashi: I am sure it’s very tasty. But, I’m vegetarian! The whole Jain family is vegetarian. Meher: Wow! That’s interesting. We know very few vegetarian families. Most of our Parsi family and friends love patrani machchi and mutton dhansak. Rashi: Did you know we speak similar languages? You speak Gujarati and I speak Marwari. Our ancestors were neighbours too! 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 97 1 2/15/2018 10:16:32 AM

QQ. What can be said about the Irani and Jain families? (A) They are both vegetarian. (B) They both enjoy non-vegetarian food. (C) They both speak similar languages. (D) Their languages are very different from each other. Remembering India is one country with many different cultures. What makes Indians so diverse? Languages, food and clothing Hindi and English are the official languages of the central government. Official languages are used by governments for their work. States choose their own official languages. The 22 official languages used in India are: • Assamese • Bengali • Bodo • Dogri • Gujarati • Hindi • Kannada • Kashmiri • Konkani • Maithili • Malayalam • Manipuri • Marathi • Nepali • Odia • Punjabi • Sanskrit • Santali • Sindhi • Tamil • Telugu • Urdu Other than these, there are 1699 languages in India. Example: Bhojpuri, Tulu, Lepcha, Marwari and many more. Do you speak a language that is not on this list? What is it? The language, food, clothing and other habits of a group of people is called their culture. 2 2/15/2018 10:16:32 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 98

Look at the map. It shows only languages used by the majority of people in different regions. United We Stand - I 3 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 99 2/15/2018 10:16:32 AM

Understanding Indians have different kinds of food and clothing, too. Read about these people from different parts of India. Find out which state they live in, their language, their traditional clothes and their traditional food. Find them and their families on the map given in the previous section. Assalam alaykum! I am Afshan. Namaste, I am Murali. • Jammu and Kashmir • Rajasthan • Kashmiri and Urdu • Hindi and Marwari • pheran • bright turbans, cotton • kulcha and rogan josh clothes with mirrors • dal baati Salemu! I am Akavi. Namaskar, I am Savita. • Maharashtra • Nagaland • Marathi • sari • Ao and English • bhakari (like a roti) and • woollen shawl bharit (made from brinjal) • meat, fish, rice and vegetables with tathu (tathu is a chutney) 4 2/15/2018 10:16:32 AM 51704995_BGM_181910053-Maple-G3-Textbook-Integrated-Term 2_Text.pdf 100