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Karnataka Board PUCPUC Science Class 11

A bullet travelling with a velocity of 16 m/s penetrates a tree trunk and comes to rest in 0.4 m. Find the time taken during the retardation.

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Question

A bullet travelling with a velocity of 16 m/s penetrates a tree trunk and comes to rest in 0.4 m. Find the time taken during the retardation.

 
Short/Brief Note
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Solution

Initial velocity, u = 16 m/s
Final velocity, v = 0
Distance, s = 0.4 m
Acceleration, 

\[a = \frac{v^2 - u^2}{2s}\]
\[\Rightarrow a = \frac{0 - {16}^2}{2 \times 0 . 4} = - 320 \text{ m } / s^2\]

Time,

\[t = \frac{v - u}{a}\]
\[\Rightarrow t = \frac{0 - 16}{- 320} = 0 . 05 \text{ s} \]
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Chapter 3: Rest and Motion: Kinematics - Exercise [Page 52]

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HC Verma Concepts of Physics Volume 1 and 2 [English]
Chapter 3 Rest and Motion: Kinematics
Exercise | Q 16 | Page 52

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