# Geometric Progression

1. Jun 8, 2009

### Chewy0087

1. The problem statement, all variables and given/known data
A ball is dropped vertically from height h onto a flat surface, after the nth bounce it returns to high h / 3^n. Find the total distance travelled by the ball.

2. Relevant equations

Sum (infinity) = $$\frac{a}{1 - r}$$

3. The attempt at a solution

I don't see the problem,

r is 1/3, a is h,

$$\frac{h}{ 2/3 }$$= 1.5h, however the problem is i'm told the answer is 2h.

Any help would be appreciated

2. Jun 8, 2009

### CompuChip

If it bounces to height h/3^n, it will also have to drop to the ground from height h/3^n again. So it always travels this distance twice, except when n = 0.

3. Jun 8, 2009

### Chewy0087

Gotcha, thank you.