If a body looses half of its velocity on penetrating 3 cm

• Work Energy

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

1. 1 cm
2. 2 cm
3. 3 cm
4. 4 cm

Answer

Using V² = U² - 2as

For the initial case, the body loose half of its velocity on penetrating 3 cm

Therefore, (V/2)² = V² - 2a*3

a = V²/8

Now for the body to come at rest the final velocity needs to be zero and the initial velocity becomes v/2.

Assuming a constant retardation and by again applying the same equation you get

s = 1 cm

The correct option is A.