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Question
A car traveling at 60 km/h, stops on applying brakes in 10 seconds. What is its acceleration?
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Solution
First convert 60 km/h in m/s.
60 km/hr =(60 X 1000)/3600 = 16.7 m/s.
This is initial velocity of car i.e u = 16.7 m/s.
As car stops in 10 seconds so final velocity is =0 m/s.
So acceleration = (v-u)/t = (0-16.7)/10 = -1.67 ms-2.
Acceleration of car is = -1.67 ms-2.
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