• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Investigating pendulums.

Extracts from this document...


Investigating pendulums


A pendulum is an object suspended from a string or light rod that is able to swing back and forth. It is a device used in such objects as clocks. It is made of a string with a bob attached to the end, this is suspended form a point where the pendulum can swing back and forth. Galileo was the first to make a theory about pendulums. He watched one of the lamps swaying, which was suspended from the ceiling of the church he was in. He noticed that as the size of the swing (arc) got smaller the time of the swing remained the same. He knew this as he timed the oscillation against his pulse. It was Christiaan Huygens that came up with the formula for calculating the period of a pendulum’s swing. One complete swing of a pendulum is called an oscillation. The time for a complete swing or arc is called a period.

We were asked to pursue an experiment with a pendulum. In this experiment I plan to investigate to see if changing the length of the string of the pendulum effects the period of the oscillation. I will do this by measuring the time it takes for ten oscillations, then divide that by ten to find the time it takes for one oscillation. I will do this at ten equally staggered lengths of string.

...read more.


















The reason I have devided the last column by ten is because the lengths of the string are in centimetres and gravity is in metres per second and the units need to be kept the same.

Quantitative prediction

I found that in the predicted results I could estimate the period of a pendulum of any given length if I had the results for one given length’s period.

If I had the period for a piece of string of 10cm, then I could find the time for one oscillation of a pendulum with a length of 20 by this formula:

T (period)=0.63 when l=10 centimetres

So as we are doubling the length we times the period by the square root of 2.


0.63 x √ 2 = 0.89

If you look up at the table of predicted results, 0.89 is the predicted period of a pendulum of a 20cm length.

This formula also works for any length you want to find. You just times the given period by the square root of the number of times bigger the length of string is you want to find the period for.

So if we wanted to find the period if the string was 50cm then we would times the period for one oscillation at 10cm by the square root of 5 because 50cm is 5 times bigger than 10cm:


0.63 x √ 5 = 1.41

As you can see from my table of predicted results, this was also correct.

Fair testing

...read more.


I think my results were quite accurate and we only had one result that was extremely different. This was our only anomaly and I think it was caused because we were nor really concentrating and being entirely accurate.

I think my results were reliable enough to draw the conclusion that the length of the string has a big impact on the period of the pendulum. As the length of the string decreased so did the period.

I think this experiment could be made more accurate if we had had more time to pursue it, we would have been more accurate with our measurements. One of the main problems we had with this experiment was keeping the retort stand steady. When the string was at its longest length the stand would wobble. We overcame this problem by putting lots of weights on the base and it eventually worked. I think that if we took more readings at each length then we could possibly draw a better conclusion.

...read more.

This student written piece of work is one of many that can be found in our GCSE Forces and Motion section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Forces and Motion essays

  1. Period of Oscillation of a Simple Pendulum

    This is the only way that accuracy can be improved without repeating the experiment many times to get an average score. The only way that the experiments can be improved is their timing methods and the conditions under which the experiments are performed.

  2. Investigating Impact Craters

    So as the vertical height dropped increases, so does the distance travelled by the ball. This is to be expected, as the ball will have some horizontal speed from the release ramp. If the graph were continued for greater heights, I expect it would begin to level off as the drag on the ball would cause it to decelerate.

  1. Damped Oscillation.

    If I made the second mark is 0.2 meter lower than the first one and took the reading, all my basic data for calculation (i.e. initial velocity) is estimation from my first approximation. As I taking more estimation, the error will be too big to make the results of this experiment unacceptable.


    By the second definition, the number 3.1415 is more precise than the number 3.14. Look at the examples below: * Examples from my results contain the results for 10cm length in which as we can see the average of my results is close to that calculated from expression but the three results are far from each other(precise but not accurate)

  1. Strength of a string practical investigation

    * Pulley: A smooth running surface for the wire, over the edge of the table. Hence this will let the string extend with force with minimal friction. * Masses: These will be used to put load on the string to give an extension reading.

  2. An Investigation to discover whether the string length of a pendulum affects the pendulum ...

    I will release the pendulum and start the stopwatch timing. 6) I will wait for the pendulum to do 10 swings, and then stop timing. As I only want the time of one swing, I will divide this time by ten.

  1. This investigation is associated with the bounce of a squash ball. I will be ...

    Some of this energy is dissipated (as heat, etc.), but some is stored in the deformed material and is released when the material relaxes. The extent to which a material stores energy under deformation is called 'resilience'. Some materials (like sprung steel)

  2. An Experiment Using a Pendulum to Find the Acceleration due to Gravity.

    > Find a suitable place to build the pendulum either from the ceiling, or on two stands between two tables to allow a meter of pendulum beneath them. A rigid structure is important otherwise energy is absorbed in the swaying of the stands.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work