Physics I lab
Lab Group 6
To determine an experimental value for gravity by electronically determining the time taken by a steel ball to drop through several known distances.
Firstly the equipment was set up in such a way that the test ball could be dropped through a distance between 1.5 and 2 meters. Then steel ball was dropped from a known distance and repeated three times for each drop distance. Then the average drop time was obtained for each drop distance. Then the graph (Time squared vs. height) was plotted with height along the vertical and then the slope of line was calculated.
The following table records the drop distances with their respective drop times. Drop Distance | First drop time | Second drop time | Third drop time | Average Drop time (t) | t2 | 1.5 m | 0.5571 secs | 0.5556 secs | 0.5572 secs | 0.5566 | 0.309 | 1.7 m | 0.5942 secs | 0.5931 secs | 0.5926 secs | 0.5933 | 0.352 | 2 m | 0.6425 secs | 0.6456 secs | 0.6435 secs | 0.6438 | 0.414 |
The error sources in this experiment which can cause the value for g to be in error are the error in measurement of the drop distance and the error in calibration of the digital timing system. If there is error in measuring the distance of the drop, it leads to an error in the experimental value of the g. In the same way, if the timing system itself has an error, it will lead to the error in calculation of the g.
The lab helped us to calculate the value of g by recording the drop time of a free falling body from a certain height. In this way the value of g was calculated to be