Equipment
- Stand
- Boss
- Clamp
- String (at least 80cm)
- 2 wooden blocks
- Pendulum
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Metre ruler
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Stopwatch
Diagram
Method
- Fix the string with the ball to a clamp as shown in the diagram above and afterwards the whole thing should look like the picture.
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Practice timing and using the pendulum, make sure you measure as soon as the string passes through the centre point then out to the right, then to the left and then back to centre, and that counts as one full period, make sure that the string stays in one plane and doesn’t wobble.
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Prepare a results table with columns l, T10, T and T2 and gather 8 sets of readings.
- Measure the Length of string.
- Release the pendulum and record for 10 complete periods.
- Adjust the length of string.
- Repeat 4,5 and 6 placing the results in the table as you continue.
Results
Graph
Analysis
Using the line of best fit and putting in a maximum gradient and minimum gradient on the graph I calculated the mean point to be (0.475, 2.12)
Using points (0.3, 1.35) and (0.65, 2.85) I will now work out the gradient using the equation below:
Using the equation I worked out the gradient to be 4.29 (3s.f)
By squaring formula we get and then rearranging the formula to solve for g we get the formula:
If we refer to the formula and compare T2 to L then that works out to be the gradient so if we put that into the formula we get: and doing this calculation we get g to be 9.21 (3s.f)
Evaluation
During the experiment I didn’t come across any major issues with the way the experiment was done, however in the beginning I was measuring the pendulum from the point it left my hand, also during the experiment I never recorded the angle at which the ball left my hand so this could have led to an error in the final result as I did not get 9.8 so the way I took the readings could have led to an error, also I did not take enough sets of readings which is a big error in the results as I only managed to take one set of readings when I should have taken multiple and got an average. However, I calculated the percentage error using the formula below to be
X 100 = 6.02 % (2 d.p)
And that is not too big as to what I thought the value would be and it relates to my hypothesis so I wouldn’t need to change it. However,
if I was to take this experiment again I would make sure that I will measure the angle that the ball is released from and that there is no change in the plane of the pendulum and make sure I take multiple sets of readings at a time.
