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Question
The graph given alongside shows the positions of a body at different times. Calculate the speed of the body as it moves from :
(1) A to B,
(2) B to C, and
(3) C to D.
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Solution
(i) The distance covered from A to B,
= 3 – 0
= 3 cm
Time taken to cover the distance from A to B
= 5 – 2
= 3 s
Hence speed,
= `"Distance"/"Time"`
= `3/3` cm/s
= 1 cm/s
(ii) The speed of the body as it moves from B to C is zero because the distance travelled is zero.
(iii) The distance covered from C to D,
= 7 – 3
= 4 cm
Time taken to cover the distance from C to D,
= 9 – 7
= 2 s
Hence speed,
= `"Distance"/"Time"`
= `4/2` cm/s
= 2 cm/s
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