hey everybody, were doing the pendulum prac to find the value of gravity (9.8ms^-2) the formula is : g = (4(pi)^2) x L/T^2 where L = length of string T = period so my question was, when u sketch this on a graph, u plot the dependant variable on the y-axis (i.e. T^2) and the independant variable on the x-axis (L), which gives a straight line upwards sloping from left to right. How do u use the gradient of this line to calculate g? do u hav to invert the gradient?
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Pendulum prac question (1 Viewer)
- Thread starter unano
- Start date
Remember that g= 4Pi^2 l/T^2
Note that the l/T^2 is your gradient from the graph you are drawing. Just make sure that T^2 is on the x-axis and l is on the y-axis.... which is correcting your incorrect set-up of the graph. I always place time on the x-axis independent variable.
Then sub the value into the above formula and multiply by 4 Pi^2 that's it nice and easy.
Of course your graph orientation is critical in arriving at the correct answer. You should get roughly a value between 9.3m/s^2 and 10 m/s^2 based on your experimental method....the closer to 9.8 the better...
Based on your graph set-up YES you would have to invert the gradient to arrive at the correct value to sub into the formula. Of course your graph would also be marked wrong as the set-up of it is incorrect.
Best of luck
Note that the l/T^2 is your gradient from the graph you are drawing. Just make sure that T^2 is on the x-axis and l is on the y-axis.... which is correcting your incorrect set-up of the graph. I always place time on the x-axis independent variable.
Then sub the value into the above formula and multiply by 4 Pi^2 that's it nice and easy.
Of course your graph orientation is critical in arriving at the correct answer. You should get roughly a value between 9.3m/s^2 and 10 m/s^2 based on your experimental method....the closer to 9.8 the better...
Based on your graph set-up YES you would have to invert the gradient to arrive at the correct value to sub into the formula. Of course your graph would also be marked wrong as the set-up of it is incorrect.
Best of luck
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