# 1D Kinematics of baseball

1. Jul 24, 2009

### pttest

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

A batter hits a pop fly straight up.
a) Is the acceleration of the ball on the way up different from its acceleration on the way down? (YES / NO)
b) Is the acceleration of the ball at the top of its flight different from its acceleration just before it lands?Yes / No?

2. Relevant equations

3. The attempt at a solution
a. There is no difference in acceleration on the way up & down.
b. Yes. I was wondering at the top of its flight the ball slows down and the ball doesnt slow down right before it lands. Am I correct?

2. Jul 24, 2009

### rl.bhat

b) No. Slowing down or speeding up depends on the direction of the velocity, not on the acceleration due to gravity, which is always in the downward direction.

3. Jul 25, 2009

### ~ak~

a) Upwards the acceleration is gravity and downwards the acceleration is gravity...the initial veloicty may be positive but the acceleration is not, once the ball is hit, it has negative acceleration.