I will keep the same person recording the time it takes for the cake case to fall. This is because people have different reaction times and this could affect the time when they stopped the stop-clock. I will keep the same stop clock to ensure that I have consistent recording times.
I will keep the same sized cake cases because smaller cake cases may fall down faster than the bigger cake cases.
I will also drop the cake cases upright because an upright cake case will fall more steadily and evenly, making the results more reliable. If the cake cases were dropped upside down then they could topple and make the results inaccurate.
We will do the experiment in the same place. The reason for this is that there could me more or less air pressure in different places
Prediction
My prediction is that, as the mass increases so will the speed in which the cake cases fall down
As the mass increases, the cake cases will fall faster due to the mass. Weight is a force and if it is increased, the object will fall down faster. To show this below is some preliminary work. This was done to find out if the parachute falls down faster or slower depending on the mass. We did this by making two parachutes. One was made slightly larger than the other was. We then attached a paper clip to the bottom of the parachutes. This was done to make the parachutes fall down steadily and to help keep the parachute together. The smaller parachute was dropped from the heights of 50cm, 100cm and 150cm. it was dropped 7 times at each height. The results were then recorded in a table of results. This method was repeated for the larger parachute.
The smaller parachute fell faster because it was denser. This made the smaller parachute heavier than the larger parachute. This is because the weight depends on the mass. This parachute had a smaller surface area so there was less air resistance.this explains why the smaller parachute fell faster.
The larger parachute had less mass so it took longer to fall. This parachute took longer to fall because the weight was spread out so it became lighter. The larger parachute also had a larger surface area so there would be more air resistance. This would mean more force slowing down the larger parachute than the smaller one.
Weight is a force and if it is increased, the object will fall down faster. This is because the speed accelerates when there is more weight. As the speed accelerates and the air resistance increases, eventually the air resistance and gravity balance. When the forces balanced, it is called a constant speed (terminal velocity).
When the mass is larger, the speed and the air resistance would take a longer time for the forces to balance. Below is the formula, which relates to the mass and weight:
F = MG
Weight Mass Gravitational Force Strength
The weight depends on the mass and the gravitational force strength. If the mass increases then so will the weight. When the weight increases, then the speed that it falls at increases. Below is an example that shows that the gravitational force strength depends on the mass.
If the gravitational field strength is 10n1Kg and the mass of the rocket is 1000 kg then to find out the weight, the formula would be:
W = M X G
W =100000 X 10
W= 1000000N
If the mass of the rocket decreased to 100000 and the gravitational force strength remained the same, the weight would be W = M X G
W =10, 0000 X 10
W= 100,0000N
From this, we can see that the weight of the cake cases will increase if the mass increases. We can also see that the weight will decrease if the mass decreases. It shows that the mass depends on the weight.
Results
Analysis
From the results, we can see that when the number of cake cases increased, the faster the cake case fell. This matches my prediction, which was that when the mass increases, the speed it falls at also increases. From increasing the mass from one cake case to two, there was a big difference in the falling time. The test with two cake cases fell down much faster than the one with one cake case. As more cake cases were added, the difference in the time they fell decreased. At first when the mass increased, the speed in which it fell also increased. This was until it gradually slowed down the difference in the time it took to fall. We did not get any significant anomalies. Most of the results fitted in with the line of best fit, which shows that the results were accurate. The Graph on these results in on graph paper.
Evaluation
From the results of the experiment, we can see that most of the averages are accurate because the difference between the lowest and highest result are not large and they are quite close together. This is apart from the results for the experiment done with six cake cases. There was a big difference between the highest and the lowest results. This shows that the results for that experiment were inaccurate and needed to be redone.
On the graph, the highest and lowest results are shown as well as the small range between them. Instead of testing the rate of fall, of the cake case five times, the rate was tested seven times to ensure that the results ere accurate.
The reaction time may have affected the experiment results. The time it took for the person to stop the stop clock would not have been exact because a reaction time would have affected it.
In the experiment, another thing that affected the result was that when the cake case were dropped not all of the cake cases were dropped at the exact point of 150 cm above the ground. This caused the results to become slightly inaccurate. It could be improved by ensuring accuracy of measurement i.e. ensuring that when the cake cases are dropped this is done at exactly 150 cm.
We could have used a clamp to drop the cake cases. This would help to ensure that the cake cases were dropped at the same height, which was 150cm. This is because it would be at a fixed height. With a person, dropping the cake case from 150cm above the ground then it could be higher or lower but by using a clamp, it would guarantee that the cake case would be dropped from a distance of 150cm above the ground.
During the experiment, the person who was stopping the stop clock changed positions with someone else. This may have affected the results slightly because both people using the stop clocks had different reaction times. The same person should have timed throughout all experiments so that the results would be more accurate.
Jessica mensah 11l
