I don’t think that adding more mass would make a difference to the pendulums time of swing because gravity is keeping the same force on it, which is keeping the time of swing the same. I also think that the height of drop will make difference to the pendulums time of swing because the higher you drop the pendulum the further it has to go, so the shorter you drop the pendulum it doesn’t have to go that far.
My final prediction will be that the shorter the pendulum the faster the time and the longer the pendulum the slower the time.
Plan
Assemble the equipment as shown above in the diagram. Make sure the mass you have is the same all through this experiment. Measure the length of the pendulum/string and write the length down in an appropriate table. You can know start the experiment. Lift the pendulum/string towards you until it’s at a horizontal level. Make sure your partner has a stop clock ready and let go of the pendulum/string and at the same time start the stop clock. Count 10 swings of the pendulum and once you have counted the 10th swing your partner should have stopped the clock, record the time in your table and do this again 4 more times until you have 5 results. So once you have your first lot of results work out the average and put it by the side of your results. Then make the pendulum/string smaller and get yourself 5 more results by doing the same as before. Record the answers and find the average. Then do this again until you have 5 lengths, 25 results and 5 averages.
In experiment it’s best to have 5 or more results so you can have an accurate calculation of the average.
Safety
To make this experiment safe you should use a G-Clamp, which holds the clamp stand on the table, to stop the equipment on the table. Also stand away from the swinging pendulum, especially if you are testing to see if mass effects the pendulums time of swing.
Fair Test
To make sure this experiment is a fair test make sure you use the same amount of mass each time, drop the pendulum/string form the same height each time and start and stop the stop clock at the correct points.
Results
This table shows my results to see whether length of string effects the pendulums time of swing.
Observation
Looking at my result I can see a few results that look different from the rest. The biggest difference that I can see is in the 36cm part, the results range from a low 14.19 seconds and go up to a high 16.06 seconds. Those results will affect the average and show that my results could be more accurate.
Conclusion
The graph of my results shows to have a slight curve. Although my results are not that accurate you can still see a slight pattern, which show the shorter the length of string the shorter the time and the longer the length of string the longer the time will be. This then shows that my prediction is correct.
Accuracy of Results
In this experiment I do not think my results were accurate because of some of the range some of the groups had. All the results except for 10cm were not always in a fixed pattern because of the way I did the experiment. It may not of always been a fair test because it is quite hard keeping the angle of drop the same. I did realise some results were different whilst I was doing the experiment, but I still wrote them down otherwise it would not of been a fair test and you wouldn’t expect your answers to be perfect there is always a few different answers. I think I should of got a few more results to show a more accurate average and the graph would have a better shape to it.
Possible Improvements
If I was to do this experiment again and had more time to do the experiment I would make the following improvements, I would get more results, to get a more accurate , average, get more lengths so I would have a better graph and I would see if anything else effects the pendulums time of swing.
