Question

A bullet initially moving with a velocity 20 m s-1 strikes a target and comes to rest after penetrating a distance 10 cm in the target. Calculate the retardation caused by the target.

February 27, 2024

Answer

According to equation of motion

v² = u² + 2aS

Given,

u = 20 m s^-1,

v = 0,

s = 10 cm = 0.1 m

Substituting the values in the formula above, we get,

0 = 20² + 2 × a × 0.1

or, 0.2 a = -400

or, a = -400/0.2 = – 4000/2 = – 2000 ms^-2

Hence, Retardation is 2000 m s^-2

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