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Class 7
Science
Motion and Time
suppose the two photographs shown in fig 13 1 an...

Question:
Suppose the two photographs, shown in Fig. 13.1 and Fig. 13.2, had been taken at an interval of 10 seconds. If a distance of 100 metres is shown by 1 cm in these photographs, calculate the speed of the blue car.

Answer:

With the help of the scale we will first measure the distance:

Suppose the distance measured is 2 cm
So, the distance covered = 2*100 = 2 m (because 1 m = 100 cm)
Time taken = 10 seconds

Speed = (distance/ time) = (200 m/10 s) = 20 m/s
Therefore, the speed of the blue car = 20 m/s.

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Question:
Suppose the two photographs, shown in Fig. 13.1 and Fig. 13.2, had been taken at an interval of 10 seconds. If a distance of 100 metres is shown by 1 cm in these photographs, calculate the speed of the blue car.

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Question: Suppose the two photographs, shown in Fig. 13.1 and Fig. 13.2, had been taken at an interval of 10 seconds. If a distance of 100 metres is shown by 1 cm in these photographs, calculate the speed of the blue car.

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Question:
Suppose the two photographs, shown in Fig. 13.1 and Fig. 13.2, had been taken at an interval of 10 seconds. If a distance of 100 metres is shown by 1 cm in these photographs, calculate the speed of the blue car.