Question

a bullet is fired from a gun with a velocity of 100m/s goes through a trunk of a tree. the bullet losses half of its k.e in the trunk. the velocity of bullet after its come out of the trunk​

Answer 1

Answer:

Explanation:The distance after which the bullet comes to rest is 0.4m.

The initial velocity of the bullet is 16m/s.

Let us say, the magnitude of retardation is a. So,

v^2=u^2+2as

0=16^2+2×a×0.4 (v=0, cause the bullet comes to rest.)

a=-256/0.8

a=-320m/s^2

Now, for time, we use,

v=u+at

0=16–320×t

-16=-320t

16/320 =t

t=0.05

Therefore, the time taken is 0.5s