What is the speed of a 10 g bullet if it starts moving with a kinetic energy of 3200 J?

Given:

m = 10 g = 0.01 kg;

Eк = 3200 J;

To find:

V -?

Decision.

We will find the bullet velocity from the formula for determining the kinetic energy of the body.

Ek = (m * V ^ 2) / 2.

After transforming the expression, we will find the required value.

2 * Ek = m * V ^ 2;

V ^ 2 = (2 * Ek) / m;

V ^ 2 = (2 * 3200) / 0.01 = 6400 / 0.01 = 640,000;

V = 800 m / s.

Answer: bullet speed 800 m / s.