# Homework Help: Free fall of stones

1. Oct 3, 2007

### lostfan176

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

A stone is dropped from the roof of a high building. A second stone is dropped 1.50 s later. How far apart are the stones when the second one has reached a speed of 11.0 m/s?

2. Relevant equations

kinematics

3. The attempt at a solution

i need help setting up the problem i dont know how

2. Oct 3, 2007

### cristo

Staff Emeritus
Well, work out the displacement of the first stone when it reaches 11m/s, then the displacement of the second stone at this time.

3. Oct 3, 2007

### lostfan176

i got the displacement of the first one as 6.17 m how do i get the second one?

4. Oct 3, 2007

### cristo

Staff Emeritus
There's no way I can tell you you're right or not if I don't see your work! Try calculating the time when the stone reaches 11m/s. Then you can perhaps find the displacement of the second stone at this time.

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