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Question
A bus running at a speed of 18 km/h is stopped in 2.5 seconds by applying brakes. Calculate the retardation produced.
Solution
We have to find the value of retardation. So,
Initial velocity,
`(u)` = 18 km/hr
= `"18(1000)"/3600` m/s
= 5 m/s
Final velocity, (v) = 0 m/s
Acceleration , `a = (v-u)/t`
Put the values in the above equation to get the value of acceleration
`a = (0-5)/2.5`
= `-2 "m/s"^2`
Thus, the retardation is 2 m/s2.
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