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Question
A bus can accelerate with an acceleration of 1 m/s2 . Find the minimum time for the bus to attain the speed of 100 km/s from 50 km /s.
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Solution
Acceleration of the bus (a) = 1 m/s2
Initial velocity (u) = 50 km/s = 50 x 103 m/s
Final velocity (v) = 100 km/s = 100 x 103 m/s
time (t) = ?
`"t "= ("v"-"u") /"t"= (100xx10^3 - 50xx10^3)/1 = ((100-50)xx10^3)/1`
t = 50 × 103 s
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