Homework Help: Projectile Motion

1. Oct 3, 2009

@d@m

1. The problem statement, all variables and given/known data
If a wood with loft 18 degrees is used to hit a ball that is in the air for 10.9 s, calculate:
(a) The distance the ball travels if its intial velociity is 18.5 m/s.
(b) The maximum height of the ball

2. Relevant equations

3. The attempt at a solution

2. Oct 3, 2009

shootingrubbe

For a:
If you know the time in which the ball is in the air for you can easily find the horizontal range. You do this because you know the initial velocity, which is 18.5 m/s [18 deg above the horizontal]. You can calculate the horizontal speed, which is always constant in this case. Then use the equation deltaX=Vx(deltaT) to find the horizontal range...

For b:
Time is independent of the vertical and horizontal directions so you can use the same time in the vertical calculations... You know acceleration in the y direction (9.8), You know the initial speed in the y direction because you can easily calculate it... And if you want to know the maximum height of the ball you know that it's speed at the top of its flight will be 0... Now you have 3 pieces of info you can use to solve b...

Hope I helped...