A bus moving at 36 km/h is brought to rest by applying brakes. If the brakes produce a uniform retardation of 0.5 m/s², how far does the bus travel before coming to rest?
PhysicsClass 9CBSEAnswered 13 May 2026
Answer
Initial velocity (u) = 36 km/h
Convert u to m/s: 36 km/h * (1000 m / 1 km) * (1 h / 3600 s) = 10 m/s
Final velocity (v) = 0 m/s (comes to rest)
Acceleration (a) = -0.5 m/s² (retardation is negative acceleration)
Using the third equation of motion: v² = u² + 2as
0² = 10² + 2 * (-0.5) * s
0 = 100 - s
s = 100 meters.
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