Question 6

Fig 8.11 shows the distance-time graph of three objects A,B and C. Study the graph and answer the following questions:

* Fig. 8.11*

(a) Which of the three is travelling the fastest?

(b) Are all three ever at the same point on the road?

(c) How far has C travelled when B passes A?

(d) How far has B travelled by the time it passes C?

Answer

(a) Object B

(b) No

(c) 5.714 km

(d) 5.143 km

(a)

From the graph, it is clear B covers more distance in less time. Therefore, B is the fastest

(b) All three objects A, B and C never come at the same point .

(c) On the distance axis:

7 small boxes = 4 km

∴1 small box = 4 / 7 km

Initially, object C is 4 blocks away from the origin.

∴Initial distance of object C from origin= 16 / 7

Distance of object C from origin when B passes A = 8 km

Distance covered by C

Hence, C has travelled a distance of 5.714 km when B passes A.

(d) Distance covered by B at the time it passes C = 9 boxes

Hence, B has travelled a distance of 5.143 km when B passes C.

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- NCERT Chapter

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