Lab Report

Pendulum Lab
Testable question:   If we pull the mass on the string back farther and farther, what affect will this have on the length of the period?
Hypothesis:   if the length of the pullback is increased, then the length of the period will be different because the hanging mass has a greater distance to cover.
Materials used:
• String
• Stopwatch
• Hanging masses
• Metal bar
• Meter stick

Steps:  
1. Get string, masses, and stopwatch.
2. Tie the string to a length of 34cm.  
3. Attach string to the metal pole via one out of the two knots.
4. Connect 100 gram mass to the second hole in the string.  
5. Pull string back 10cm, 15cm, 20cm, and 25cm.
6. Once the string is pulled back, release it and start timing after two seconds.  
7. Divide this time by 10 (10 being for the 10 periods it is moving).
8. Repeat steps 5-7 for the last three lengths of pullbacks.

                                                                                      Data Table
Pullback       Length Trial One Trial Two Trial Three Average
10cm 1.219 1.225 1.209 1.218
15cm 1.228 1.232 1.218 1.226
20cm 1.219 1.225 1.232 1.225
25cm 1.24 1.24 1.243 1.241

Graph of data


Analysis:
My analysis of the data says that the length of the pullback does matter for the time of a single period of a pendulum.   As my graph and table show, the longer a person pulls the hanging mass back, the greater time it takes for a complete period to take place.   There might be some human error in this experiment, but the errors that took place wouldn’t have had a very large impact on the test results.
Conclusion:
My conclusion is the same as my hypothesis, stating if the length of the pullback is increased, the hanging mass will have a greater distance to cover, therefore making a greater time for a complete period.   The human errors that occurred were probably extremely small, such as the reaction time of the person timing.   This person could have been off a few milliseconds, but in...