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Question
A bullet going with speed 350 m/s enters a concrete wall and penetrates a distance of 5.0 cm before coming to rest. Find the deceleration.
Solution
Initial velocity, u = 350 m/s
Final velocity, v = 0
Distance travelled by the bullet before coming to rest, s = 5 m
\[\text{ Acceleration, a } = \frac{v^2 - u^2}{2s}\]
\[\Rightarrow a = \frac{0 - \left( 350 \right)^2}{2 \times 0 . 05} = - 12 . 2 \times {10}^5 \text{ m } / s^2\]
∴ Deceleration = 12.2 × 105 m/s2
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