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3 years ago

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A van is traveling with an initial velocity of 12 m/s. The driver takes a time of 45 seconds to speed up to a velocity of 20 m/s

. How much distance did the van cover during this time?

1 answer:

Rufina [12.5K]3 years ago

4 0

Initial velocity=u=12m/s
Final velocity=v=20m/s
Time=t=45s

$\\ \rm\hookrightarrow Acceleration=\dfrac{v-u}{t}$

$\\ \rm\hookrightarrow Acceleration=\dfrac{20-12}{45}$

$\\ \rm\hookrightarrow Acceleration=\dfrac{8}{45}$

$\\ \rm\hookrightarrow Acceleration=0.1m/s^2$

Now

Distance=s

$\\ \rm\hookrightarrow v^2-u^2=2as$

$\\ \rm\hookrightarrow (20)^2-12^2=2(0.1)s$

$\\ \rm\hookrightarrow 400-144=0.2s$

$\\ \rm\hookrightarrow 256=0.2s$

$\\ \rm\hookrightarrow s=\dfrac{256}{0.2}$

$\\ \rm\hookrightarrow s=1280m$

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