1. Nov 2, 2004

### Format

How do you find an orbital radius of an object around earth with its mass and Orbital Period?

2. Nov 2, 2004

### UrbanXrisis

Last edited by a moderator: May 1, 2017
3. Nov 2, 2004

### Format

Awsome, thx man. Some of these equations ive never seen before help alot lol

4. Nov 2, 2004

### UrbanXrisis

Never doubt the power of Mr.Google! :tongue2:

:rofl:

5. Nov 2, 2004

### Format

Kenetic/Potential Energy

When an object eaves the surface of the ground with a certain amount of Kenetic Energy and reaches a max height what does the Potential energy equal to?

I know the equation Ep = -Gmm/r but the question says it leaves the surface with 15 J of Kenetic energy.

6. Nov 2, 2004

### Parth Dave

When it reaches a max height, what happens to the kinetic energy?

7. Nov 2, 2004

### Format

It equals 0?

Does that mean potential energy is equal to it? or negative?

8. Nov 2, 2004

### UrbanXrisis

The potential energy at its max height is equal to the amount of kenetic energy the object has just after it leaves the ground

9. Nov 2, 2004

### Format

What about in orbit? How do you solve for Ep when you have Ek if you know the acceleration due to gravity and the mass?

Last edited: Nov 2, 2004
10. Nov 2, 2004

### UrbanXrisis

In orbit with constant velocity? or is it accelerating? In space, there is no acceleration due to gravity because there is no gravity.

11. Nov 2, 2004

### Format

Its orbiting the earth, and is at a point where gravity is equal to .233 m/s²

12. Nov 2, 2004

### UrbanXrisis

I believe the equation you're looking for is:
Gravitational Potential Energy U = mg ( yf - yi ) = mg y

However, I'm not quite sure what you're asking

13. Nov 2, 2004