# Homework Help: Help on Ballistic Pendulum Angle

1. Oct 14, 2008

### Naldo6

1. The problem statement, all variables and given/known data

A bullet (m = 0.029kg) is fired with a speed of 95.00m/s and hits a block (M = 2.40kg) supported by two light strings , stopping quickly. Find the height to which the block rises.

The correct answer is 6.56E-02 m

BUt the next question is:

Find the angle (in degrees) through which the block rises, if the strings are 0.50 m in length.

i dont know how i get that angle... could anyone help plz?....

2. Oct 14, 2008

### aimslin22

I think if you draw a free-body diagram and break each string into x and y components. you could use trig.

Sorry, don't know now exactly if this helps, but maybe it will.

3. Oct 14, 2008

### Naldo6

nop... it doesnt function because the trangle formed isnot a rectangle one...

4. Oct 14, 2008

### Naldo6

anyone know how to find that angle?....

5. Oct 14, 2008

### Naldo6

yes i got it....

L - L cos(angle)= h

then we get:
angle = inverse cos ((L - h)/L )

for this exersice the correct answer is 29.68