I predict, that as the mass increases, the time taken for a full oscillation will increase, as there will be more weight.
Method
The experiment was setup on the pendulum at a fixed length. To make this possible we had the length of the string and its maximum extent in length so that we had a set length that was easy to remember, and if we had to redo our test or repeat our actions then we could easily pick up a stable and unchanging measurement.
The full experiment was conducted in the following manner:
- Set up the apparatus, with support from a teacher/technician.
- Use the clamp to secure the spring, so the top hook does not move about, and the results are not affected.
- Collect 9 100g masses, and begin by putting on 1 100g.
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Keep the length of wire at 15cm, throughout the whole experiment.
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Take the weight(s) along with the wire, to one side, stretching it as much as possible.
- Make sure the stopwatch is ready at 0.00s, and release the wire, pressing the start button on the stopwatch at the same time.
- Count 5 full oscillations, and press the stop button on the stopwatch precisely at the same time.
- Repeat this four more times, to give you five results, and then work out an average, for each set of results.
- Repeat this method for 100g, 300g, 500g, 700g, and 900g weights.
- Plot your results on graph paper.
Table of Results
Prediction
My prediction is that the more weight that is added to the bottom of the spring, the more energy is stored, and therefore will create larger oscillations. This is because according to my theory, the heavier the mass put on the spring, the larger the extension will be. So, if this is correct, there will be more energy, therefore resulting in larger oscillations.
Evaluation
In my opinion, the experiment went fairly well. I managed to obtain a full set of results, which were mostly accurate, and which I managed to make good use of. I was initially surprised at how easy the experiment went, and how I managed to almost instantly obtain accurate results.
This investigation has been successful because I have completed my aim and showed this by producing a graph with time against mass.
Although the majority of results were within range, I believe I could have made the experiment even more successful. This is due to the few outliers there were.
I could have possibly narrowed the gaps between the masses, by using 50g masses instead of 100g, in order to obtain a larger set of results.
The second way I could have improved my experiment, is to increase the number of readings taken to possibly 7 or 10. This would help me achieve more reliable results, and increase the reliability of my readings.
The accuracy of our results could also have been enhanced by carrying out more preliminary tests. This would help in the way in which I carried out my experiment, as well as helping me get used to the various mass and springs.
I could have also used more precise measuring devices, such as a digital data logger. This would have enabled us to record time to a hundredth of a second, therefore improving our results.
Another way, in which I could have improved my overall experiment and results, is by conducting the experiment in a better environment. This way, there would be no other equipment, and fewer distractions.
The last thing I could’ve done would be to amend my graphs. So, instead of drawing a line of best fit, I could’ve drawn a curve of best fit instead, seeing as the graph itself was in the shape of a curve. Not only would this have been easier to look at and analyse, but it would reduce the number of anomalies created.
We could also have had a stand or something similar to hold the pendulum in place before it drops, thus ensuring it was from the same spot each time. If I were to extend my investigation, I would provide additional evidence to back up my conclusion and prediction such as changing the length of the wire.
List of Apparatus
In the experiment, I used a range of equipment.
The following is a list of all the equipment I used:
- Protractor
- Stopwatch
- Wire
- Meter ruler
- Weights
- Standing Clamp
Precautions
The safety precautions I took were as follows:
- Ensure the experiment is carried out on a sturdy table, to avoid any equipment falling over.
- Make sure the spring is secured properly to the clamp, so know weights come off.
- Ensure there is no other equipment surrounding the experiment, such as bags, etc.
- Be alert and proceed with caution at all times in the lab. Notify the teacher immediately of any unsafe conditions you observe.
- Ensure the spring is not loaded beyond the elastic limit.
Conclusion
After analysing my results, I have come to the conclusion that the longer the weight of the mass, the longer per 5 oscillations.
I immediately noticed from my graph and table of results, that as the mass became heavier, the time per oscillations increased, thus suggesting my prediction is correct.
This therefore shows there is a strong correlation between weight of the mass, and the time per 5 oscillations.
In order to complete my graph of curve of best fit, I divided the average time by 10.
Then in order to calculate the line of best fit, I squared the results in the curve of best fit.
After looking at my graphs, I can see there are a few anomalies, particularly on the graph with the curve of best fit. Other then this, I believe my results are fairly accurate, thus suggesting my experiment, on a whole was done well.
Due to the lack of major spread in my data, I do not feel the need to include error bars in my graph.
I believe the results on the graph with the line of best fit, were particularly well. There is only one slight anomaly at 300g, meaning that the results are not fully perfect. This is not hugely significant however; as the straight line is in line with 0g meaning the experiment was fairly successful.
PHYSICS COURSEWORK
KASIM HASSAN
11W
