# Homework Help: Still don't get Impulse

1. Dec 10, 2008

### harvellt

1. The problem statement, all variables and given/known data
A ball is moving toward a batter at 32m/s and weighs 0.15kg. After the batter hits it goes 105.0m at an initial angle of 52 degrees. What is the magnitude of the impulse the ball receives in the collision with the bat, and what is the direction of the impulse?

[b2. Relevant equations[/b]
I=MV+MV'

Xmax=(2V2 sin $$\phi$$ cos $$\phi$$)/g

3. The attempt at a solution
I am having trouble finding the initial velocity of the ball after the collision. I tried using the second equation and found the velocity to be 32m/s. Is it wrong to use that formula to find the original velocity?

2. Dec 10, 2008

### mukundpa

What it means ? velocity of displacement?

3. Dec 10, 2008

### harvellt

The ball leaves the bat at a angle of 52 degrees and travels a distance of 105 meters befor it lands, neglecting the height of the collision.

4. Dec 10, 2008

### mukundpa

OK, now can you find the velocity of projection. you have the angle of projection and the range.

5. Dec 10, 2008

### rl.bhat

Use projectile equation. In that angle of projection is 52 degree and range is 105 m. And find velocity of the ball with which it leaves the bat.

6. Dec 10, 2008

### rl.bhat

Yes. Velocity of the ball hitting the bat and leaving the bat is nearly equal. (32 m/s and 32.6 m/s). Now what is angle with which the ball hits the bat?

Last edited: Dec 10, 2008
7. Dec 10, 2008

### mukundpa

yes using equation of X maximum you can find the

8. Dec 10, 2008

### harvellt

Thank you all so much I got it my major problem after I found the V0 was a sign mistake. I forgot the fact that the x velocity needed to have opposite signs, and now I have it.