∙ The angle at which the pendulum is released.
We could keep this experiment a fair test by changing only one variable at any one time.
Apparatus
∙ String ∙ Plasticine
∙ Clamp ∙ Stand
∙ Wood ∙ Weighing scales
∙ Ruler ∙Protractor
∙ Stopwatch
Diagrams
Method
In the test I will use a plasticine ball that weighs 20 grams, I will then increase the mass by 5 grams to get a series of results. The length of the pendulum string will be 40 cm long. The Angle of the swing will be 30°; I will be doing 1 oscillation. To find the average time for one oscillation I will repeat the experiment 3 times with each mass.
Safety
Some Hazards within my experiment could be;
∙ The stand could fall of the work surface and injure someone,
∙ When manoeuvring around the classroom if I’m not paying attention I could nock over someone’s experiment.
∙ If not attached appropriately the Plasticine could come of the string.
To avoid any hazards I will pay very close attention to my surrounding.
Prediction
I predict that the results will all be very similar, I think this because as the weight increases so does the distance it travels when oscillating meaning the plasticine travels further but it also does this at a higher speed meaning the overall time periods should not vary to much.
Conclusion
I have come to the conclusion that changing the mass as a variable in my particular pendulum investigation does not change the overall outcome of the experiment in terms of time periods, this was what I had predicted would happen and the reason for this is the fact that when oscillating, the bigger the mass on the end of the pendulum the further the pendulum will travel when oscillating but due to the increased weight the speed the pendulum travels at increases to meaning the time periods don’t vary very much.
Evaluation
If I was to do my experiment again when repeating it I would change several things, firstly I would change the variable I tested, I would not have chosen mass I would have chosen the length of the pendulum string the reason behind this is that the outcome of the experiment would be much simpler it would have a clearer and more obvious outcome making my experiment more successful in terms of what I have found out.
The second thing I would change would be the amount of oscillations I would test to get the time taken for the pendulum to oscillate, I would time for more oscillations making the overall outcome of each time a more accurate one therefore making my experiment more successful.
By
Martin Willan