# Easy momentum/ kenitic

1. Mar 23, 2009

### tnutty

I know that :

kinetic energy of something = P^2 / 2m , or momentum squared over 2m

why so?

I see that taking the integral of mv dv = kenitic.

can you prove this to

2. Mar 23, 2009

Staff Emeritus
You know p in terms of m and v. You also know E in terms of m and v. This should get you started.

3. Mar 23, 2009

### dE_logics

KE = $$\frac{1}{2} mv ^ 2$$

= $$\frac{1}{2} pv$$

= $$\frac{1}{2} \frac{pmv}{m}$$

= $$\frac{1}{2} \frac{p ^ 2}{m}$$