# Homework Help: A quaterback throws a football towards a reciever with an initial speed of 22m/s,

1. Sep 14, 2007

### ahsanmhamid

a quaterback throws a football towards a reciever with an initial speed of 22m/s, at an angle of 34 degrees above the horizontal. At that instant, the reciever is 21 m from the quarterback. The acceleration of gravity is 9.8 m/s ^2. WIth what constant speed should the reciever run in order to catch the football at the level at which it was thrown? Answer in units of m/s.

2. Sep 14, 2007

### TimNguyen

What are the important equations for projectile motion? There should be two you should be using, one for the horizontal direction and one for the vertical.

3. Sep 14, 2007

### Vijay Bhatnagar

Applying the equations determine range R and time of flight T of the football. To catch the football, the reciever must cover a distance (21 - R) m in time equal to time of flight T. Speed of reciever = (21-R)/T.

4. Sep 15, 2007

### ahsanmhamid

what does the variable R represent?

5. Sep 15, 2007

### Vijay Bhatnagar

R represents the horizontal distance covered by the projectile.