# Simple Intro Physics question

1. Sep 7, 2005

### Grandmas

To many this would be a simple plug it into equation problem. But for some reason this just isn't clicking for me. Here's the problem:

An open elevator is ascending with a constant speed V of 32ft/sec. A ball is thrown straight up by a boy in the elevator when it is a height h of 100 feet above the ground. The initial speed of the ball with repect to the elevator is Vo= 64ft/sec. (A) What is the maximum height attained by the ball? (B) How long does it take for the ball to return to the elevator?

I don't know where to start or what to plug in, please help me out, much appreciated and thanks.
~Grand

2. Sep 8, 2005

### snooper007

(A) $$\frac{64 \times 64}{2G}$$
G is the newton acceleration constant, in international units, it is $$9.8 meter/sec^2$$.
I don't know how to convert to your unit, ft! you must convert G to ft.
(B) $$\frac{64}{G}$$

3. Sep 9, 2005

### Mk

In physics you should use SI units anyway.