# Making sense of data - For my Physics coursework I was given the results of an experiment.

Physics coursework –

Making sense of data

## For my Physics coursework I was given the results of an experiment, which involved rolling two differently sized balls (initially 3 however one was marble and did not work with the light gate because it gave 2 readings as it reflected light) one small, silver, with a diameter of 0.006 m and weighing 0.00708 kg and one large, slightly rusty, with a diameter of 0.011 m and weighing 0.01672 kg, down a ramp from different heights and measuring the velocity they travelled at using a light gate, connected to a computer which worked out how long the light beam was broken for. The diagram bellow shows how the experiment was set up:

I then had to decided what I was going to use these results for, I decided that I would use them to see if the height the ball is dropped from effects the amount of energy change by working out the difference of potential energy and kinetic energy of the ball. This would mean I would have the amount of energy at the start from calculating potential energy, then the amount of energy at the end of rolling it down the ramp by calculating kinetic energy. I could then find the amount of energy change by subtracting kinetic energy from potential energy. I will calculate the potential and kinetic energy from the mean of 3 tests per experiment.

To calculate potential energy I will use the formula:

PE = mass (kg) x gravity (N) (using 9.8) x height (m)

To calculate kinetic energy I will use the formula:

KE= 0.5 X mass (kg) x velocity2 (ms-1)

In theory I should predict that the kinetic energy would stay the same as the potential energy is however when rolling down the ramp energy will be lost through moving air out the way, in sound energy of the ball rolling, and in friction causing heat energy. This means I predict that as the ball is dropped from a higher height there will be more energy lost, as there is more distance for it to loose the energy. I also predict ...