Question

if a body loses half of its velocity on penetrating 3 cm in a wooden block then how much will it penetrate more before coming to rest

Answer 1

Let the initial velocity of the body be u. Its velocity becomes u/2 after penetrating 3 cm in the block. We can calculate the deceleration of the body using these.
v²= u² +2as
u²/4 = u² + 2a×3
-3u²/4 = 6a
a = -u²/8

Now, we can calculate the distance the body travels till it comes to rest.

v² = u² + 2as
0 = u² +2×(-u²/8)×s
u² = u²s/4
s = 4 cm

Therefore, the body penetrates 1 cm (4-3=1cm) more before coming to rest.

I hope you understand the concept.
All the best!

Answer 2

Answer:

Explanation:

Ans : - 4 cm

more information in the attached pic