Help Momentum

1. Nov 12, 2007

Sucks@Physics

Help!!! Momentum

A ball, of mass 100g, is dropped from a height of 16m. Its momentum when it strikes the ground is?

How do you do this calculation?

Thanks!

2. Nov 12, 2007

catkin

What have you tried? Do you know what momentum is?

Last edited: Nov 12, 2007
3. Nov 12, 2007

Dick

First you compute the velocity. Then you remember the definition of momentum. Get started with the first part.

4. Nov 12, 2007

Sucks@Physics

Dont' I have to have time to calculate velocity? i know p=mv i just dont know the velocity

5. Nov 12, 2007

Vidatu

Look in the formulas sticky, at the top of this page. There''s one in there which you can use to solve this.

6. Nov 12, 2007

Sucks@Physics

i do not see the formula??

7. Nov 12, 2007

Vidatu

$$v^2 = v_0^2 + 2 a \Delta x$$

$$\Delta x$$ is the displacement.

8. Nov 12, 2007

Sucks@Physics

i end up getting 313.6 m/s that can't be right? a= gravity correct?

9. Nov 12, 2007

Vidatu

You're putting in some formula wrong. Show whet you are doing, and we'll tell you where you messed up.

10. Nov 12, 2007

Sucks@Physics

0+(2x9.8x16) = 313.6

11. Nov 12, 2007

Vidatu

Check the formula again.

12. Nov 12, 2007

Sucks@Physics

grrr im stupid

13. Nov 12, 2007

patrickking

Yah A= -9.80 (Or 9.80 down) Thats the gravational force pulling down.