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A bullet is fired normally on an immovab...

A bullet is fired normally on an immovable wooden plank of thickness 2 m. It loses 20% of its kinetic energy in penetrating a thickness 0.2 m of the plank. The distance penetrated by the bullet inside the wooden plank is

A

0.2m

B

0.8m

C

1m

D

1.5m

Text Solution

Verified by Experts

The correct Answer is:
C
The wood offers a constant retardation. If the bullet loses 20% of its kinetic energy by penetrating 02 m. It can penetrate further into `4xx 0.2 = 0.8 m` with the remaining kinetic energy So the total distance penetrated by the bullet is `0.2 + 0.8 = 1 m`
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FULL MARKS-WORK, ENERGY AND POWER-Additional Question Solved (I. MCQ)
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  2. A body of mass 5 kg is initially at rest. By applying a force of 20 N ...

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  5. The kinetic energy is conserved in

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  7. In inelastic, which is conserved

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  9. When bubblegum is thrown on a moving vehicle, it stricks is an example...

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  10. Elastic collision is due to

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  11. Inelastic collision is due to

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  12. If the velocity of separation is equal to the velocity of approach , t...

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  13. For elastic collision, coefficient of restitution is

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  14. For inelastic collision coefficient of restiitution is

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  15. For perfectly inelastic collision, coefficient of restitution is

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  16. For perfectly inelastic collision, coefficient of restitution is

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  17. The ratio of velocities of equal masses in an inelastic collision wit...

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