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Question
A bus was moving with a speed of 54 km/h. On applying brakes it stopped in 8 seconds. Calculate the acceleration.
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Solution
(b) We have to find the value of uniform acceleration. So, Initial velocity
(u) = 54 km/hr
= `"54(1000)"/3600` m/s
= 15 m/s
Final velocity (v) = 0 m/s
Time taken(t) = 8 s
So acceleration, `a = (v-u)/t`
Put the values in the above equation to get the value of acceleration
`a = (0-15)/8`
= -`1.875 "m/s"^2`
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