28-Aug-2014: Free Fall Lab

Purpose:

Our purpose in this lab is to prove that gravity is 9.8 and a free fall object has an acceleration of 9.8m/s.

Lab Setup

 The apparatus above was used to mark the spark sensitive tape as the object is free falling.

This spark sensitive tape shows the distance the object was at a time. This data could be used to obtain a Distance vs Time Graph and Velocity vs Time Graph. 

Procedure:

1). First we align the spark sensitive tape with a meter stick and recorded the distance where each spark was marked. (Tip: align the 0 cm mark with the first dot then record your data from there)

2). Next, open a new excel worksheet. Column A is Time, Column B is Distance, Column is change in distance, Column D is Mid-interval Time, and Column E is Mid-interval Speed.

3). The first data point across is 0 because that is the starting point. Except of Mid-interval time, enter A2+1/120.

4). Enter the rest of the data including the distance and time. The time interval would be 1/60.

Data:

Below is a screenshot of our data table and graphs. Time vs Distance is a exponential fit and Mid-interval Speed vs Mid-interval Time is a linear fit. These data points are valid because they show that the accelerating is very close 9.8m/s. 

Summary:

We measure gravity by using the an apparatus that generates sparks and marks the position of the object as it free falls. Using the data collected from the spark sensitive tape, we were able to prove that gravity for a free falling object is 9.8m/s by plugging in our data into excel to find a fit for our graphs.