Activity 8.3 Let us identify (Page 112) Look at the wall clock shown in Fig. 8.9 carefully Class 7

Activity 8.3 Let us identify (Page 112) Class 7

Activity 8.3 Let us identify (Page 112) Class 7

Question 1.

Look at the wall clock shown in Fig. 8.9 carefully. What is the smallest interval of time you can measure with it?

Answer:

One second is the smallest interval of time that we can measure using this clock.

Question 2.

For races covering the same distance, we can tell who was faster by measuring time. But how can we tell that when comparing races for different distances?

Answer:

To compare races of different distances, we compare speed. Divide the total distance by the total time taken to complete the distance. Calculate each racer's average speed, whoever has the higher average speed consider faster.

Question 3.

What do we mean when we say something is moving fast or slow? Suppose you are watching a 100 -metre race on a straight track. All the players begin from the starting line together but after sometime they are not running together (Fig. 8.10, see textbook). How do you decide who is running faster amongst them?

Answer:

Someone who is ahead of others at some instant of time, is running faster than them. Hence, someone who has covered more distance within the same time is running faster. The distances moved by objects in a given interval of time decide whìch one is faster or slower.