A car accelerates from 32.0m/s to rest with an acceleration of -3.20m/s^2. What is the car's displacement from t=2 to t=3 seconds? What is the car's displacement from t=4 to t=5 seconds?

1 Answer
Oct 30, 2017

A)24m
B)17.6m

Explanation:

1. From t=2 to t=3 ,

First, we'll find the velocity at time 2s.

v=u+at
=32m/s+(-3.2)m/s^2 *2s
=25.6m/s

Now, we'll substitute that in the displacement equation, with time being 1s (the time between t=2 to t=3)

S=ut+0.5at^2
=25.6m/cancels*1cancels+0.5*(-3.2)m/cancels^2*(1cancels)^2
=24m

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2. From t=4 to t=5 ,

We'll follow the same method.

v=u+at->" speed at "4 s
=32+(-3.2)4
=19.2m/s

S=ut+0.5at^2
=19.2*1+0.5*(-3.2)*1^2
=17.6m