# Homework Help: Finding g given height & time

1. Sep 5, 2007

### ccsmarty

Calculating "g" given height & time

This problem is part of a physics lab. I need this step to finish the other parts of the lab, and I can't figure out how to do this step.

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

Using the best estimate and uncertainty for the fall time, calculate the value of "g" with the appropriate number of significant figures.

fall time = 0.4249 +/- 0.0001 seconds
height = 1.002 +/- 0.005 meters

2. Relevant equations

acceleration = height/(time)^2 (?)

3. The attempt at a solution

I'm not even sure where to start...
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

Last edited: Sep 5, 2007
2. Sep 5, 2007

### learningphysics

Use the formula

d = v1*t + (1/2)at^2

apply this formula to this situation...

3. Sep 5, 2007

### HallsofIvy

Since in this problem, the object is "falling" (i.e. not thrown up or down), v1= 0. Put in the given values for d and t and you have a single equation to solve for a (for gravity problems, a= v).

4. Sep 5, 2007

### ccsmarty

Thanks to both of you for your help :)