# Homework Help: Gravity help

1. Sep 5, 2006

### emma123

If an object is thrown vertically upward on the moon how many times higher will it go than it would on earth if they both have the same initial vel.

Acceleration on moon is 1/6 of what it is on earth

I need some help on solving this. Thank You

2. Sep 5, 2006

### tony873004

Pick an initial velocity, let's say 9.8 m/s to keep it simple. On Earth do you know how high it would go?

3. Sep 5, 2006

### emma123

how do you calculate to get the height?

4. Sep 5, 2006

### tony873004

Do you have kinematics formulas? Is this a high school class?

5. Sep 6, 2006

### emma123

yes but i don't have the formulas or the textbook with me but only the questions because this is homework over the summer

6. Sep 6, 2006

### tony873004

Without doing any math, do you have a guess as to the answer?

7. Sep 6, 2006

### emma123

is it 96.04m?

8. Sep 6, 2006

### tony873004

no. but I didn't mean the answer to my question in the 2nd post of this thread. I meant can you guess at the answer to your original question?

9. Sep 6, 2006

### emma123

it'll go six times higher?

10. Sep 6, 2006

### tony873004

That wasn't too hard, was it? :)

11. Sep 6, 2006

### emma123

o really? thats the right answer but can u teach me how to do it mathematically? because i have to show my work and steps in how to get the answer

Last edited: Sep 6, 2006
12. Sep 6, 2006

### tony873004

Without doing your work for you, I can't. But there's a few threads similar to this one posted today on this same forum that will give you all the formulas you need. Get the formula, and determine why distance is linear.

13. Sep 6, 2006

### emma123

can someone provide me the formulas i can't seem to find any of them in this forum?

14. Sep 6, 2006

### HallsofIvy

If the acceleration is -a (negative because it is downward) and there is an initial velocity v0 upward, the velocity at time t is v= v0- at and the height is v0t- (1/2)at2. Can you figure out from that the time until the highest point and that height, both in terms of a and v0?