The preliminary work involved me testing out how to do the experiment and to record a few results to compare with the final ones. My range for the preliminary work was from 200 centimetres to 25 centimetres, measured at 25 centimetre intervals. I found that this didn’t give me very many results, so I decided to make the intervals smaller as said above.
Results Of Preliminary Experiment
Method To Preliminary Experiment
My method involved the apparatus being set up. I used one stand with a clamp, and two metre rules stuck together, one on top of another. The most bouncy of three golf balls was chosen, and were dropped from a series of different heights, three times each to obtain an average.
Apparatus
Method
The clamp was placed on the work top, and two metre rules stuck together were clamped to the stand on place. Once a range of different heights was decided, the golf ball was dropped from each of them by someone else so I could read off the height that the ball bounced back to accurately. The ball was dropped from the same height three times so an average could be taken, and to make sure there were no anomalies, it was done for accuracy. Also to make sure it was a fair test, I made sure the result I was reading off was the point at which the bottom of the ball came, otherwise if I had read off where the top of the ball had come to I would have had to measure the diameter of the ball and taken it away from the result so it was accurate.
My safety precautions were to make sure there was enough space to sit on the work surface to prevent the likelihood of falling off. I also made sure to golf ball wasn’t anywhere near anybody else’s experiment
So it didn’t interfere or fall into someone’s cooling water experiment, possibly causing hot water or oil to splash out at them, which could be very dangerous.
Obtaining Evidence
The best way to record my results, I decided was to draw out a table with the decreasing height against the number of times the ball was dropped and work out the average, which I could then use to plot a graph of the initial height dropped from against the height it bounced back to.
Results To Final Experiment
Analysing and Considering Evidence
My conclusion is that the difference between the heights is very small, but I have noticed that at greater height the greater the difference is, meaning that the greater the height the shorter the distance the ball can bounce back to. This is probably due to gravity and air resistance. As in if the ball is dropped from a great height, gravity will prevent it bouncing back so high, but as the ball is dropped from a shorter distance from the ground, the difference becomes smaller, showing that the closer the ball is from the ground, the easier it can bounce back to a height close to the initial one.
My original prediction was quite right in the fact that I predicted that the higher the height the ball was initially dropped from the higher it’ll bounce back to. I didn’t realise that it may not bounce back to a height close to the initial one, when the distance from the ground is great, and that it does manage to bounce back to a height similar to the initial when the distance from the ground is shorter.
Evaluating
I think my results are accurate and reliable. All the points do lie close to the line of best fit, and the repeat readings are all very similar. I took an average for all to make it more accurate, easier and clearer for the graph. There were no anomalies as such. The first time I did the experiment and plotted a graph with the readings, they didn’t lie all that close to the line of best fit. But once I re did the first few, of the when the ball was dropped from the highest heights the results turned out well.
I think my procedure was suitable and I don’t think any changes in particular could have been made to improve the experiment. I do think that I could have investigated more into the gravity or interference with the ball bouncing back as high as it was dropped from at high heights, I could have checked if this would have continued in this way if I had dropped the ball from a few more greater heights.
I do think the evidence was good enough to support my conclusion, as it showed me that there must be something interfering with the ball bouncing back so high when it was dropped from such a height.