Question

A bullet of mass 20g is moving with a velocity of 400m/s it strikes the target and penetrates 10cm to it and comes to rest
Calculate :
i) The retarding force offered by the target
ii) If the thickness of the target is reduced to 6cm , calculate at what speed will the bullet emerge out of the target.
No Spam please​

Answer 1

Answer:

Explanation:From formula of motion

v²-u²=2as

a=v²-u²/2s

Substituting

v=0m/s

u=400m/s

s=1/10m

We get acceleration as

-8*10⁵m/s²

F=m*a

F=20/1000kg*8*10⁵m/s²

F=-16000N

Hence 16000N is the retarding force

If thickness reduced to 6cm then

From formula

v²-u²=2as

In this case we have to find out v hence

u=400m/s

S=6cm

a=-8*10⁵m/s²

v=root of 2as+u²

Substituting values mentioned above we get

v=252m/s approx

The bullet will emerge out at a speed of 252 m/s

Hope this helps you sorry for giving wrong ans before