Velocity-time graph (Fig.) shows motion of a cyclist. Find (i) its acceleration (ii) its velocity an

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7. MOTION

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The velocity-time graph (Fig.) shows the motion of a cyclist. Find $(i)$ its acceleration $(ii)$ its velocity and $(iii)$ the distance covered by the cyclist in $15\,\sec $.

A

$0$, $20\, ms ^{-1}$, $300 \,m$

B

$10$, $20\, ms ^{-1}$, $30 \,m$

C

$0.5$, $20\, ms ^{-1}$, $0.30 \,m$

D

$0$, $0.2\, ms ^{-1}$, $300 \,m$

Solution

$(i)$ since velocity is not changing, acceleration is equal to zero.

$(ii)$ Reading the graph, velocity $=20\, ms ^{-1}$

$(iii)$ Distance covered in $15\,\sec $, $s = u \times t =20 \times 15=300 \,m$

Standard 9

Science

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