3.I made sure the stop clock was ready to start, meaning that it was set on 00:00.00
4.Next I placed the trolley on the ramp at the black
5.Then I Presses the stop clock when the trolley was released.
6.I Stopped timing when the whole trolley came of the ramp.
7. Finally take down result.
8.I repeated the experiment twice for each height. (10cm, 20cm, 30cm, 40cm, 50cm, 60cm)
Making it a fair test
I made the experiment a fair test by using the same trolley, ramp and stop clock. I also took the test twice for each height so that we had two sets of data to take an average from. To make it fair test I also made sure that I increased the height of the ramp by 10cm each time by readjusting the clamp. Lastly I made sure that I started the trolley from the same place each time on the ramp, and that I started the stop- watch when I let go of the trolley and when the trolley came fully of the ramp. Also I made sure that my evidence collecting was good enough to make a solid conclusion because they followed a positive trend as I collected.
The outcome
As I predicted the the experiment proved that the higher the ramp the faster the car would go. For example when the ramp was 10 cm tall the average speed was 0.68 miles per second but when it was 60 cm tall the average speed was 1.996 miles per second.
What we could of changed and why.
Over all I feel that the apparatus that we used was reliable and we didn’t have any faults when conducting are experiments. But if I redone the experiment I would improve it by repeating the experiment at least 3 times, to get more accurate results. I would also take more readings from higher heights, so that I could try and come to a firm conclusion on the relationship between the height of the ramp and the change in speed. This is because I could have got more accurate
results and more points to plot and see what patterns had occurred
within the experiment. I also think that if we re done the experiment we could see if the weight of the car would affect the speed so we could use different cars with different masses. Also if I was going to do this investigation again I could try experimenting with different surfaces, which the trolley would go down, rather than just a smooth surface.
Pattern of graph
The pattern on the graph shows steady acceleration on the trolley at
each chosen height. The graph also shows that the relationship between
the ramps increasing in height the change in speed does increase as
well. The graph also shows that the relationship between the height of
the ramp and the change in speed is NOT directly proportional, but
instead just proportional.
Conclusion
ANALYSIS
My results show that when I made the ramp higher the car went faster down it. This is because gravity is pulling the car straight down and friction is puling the car back up the ramp, opposite to direction of motion. The ramp is pushing the car straight up in the opposite
direction of gravity. The ramp is also pushing it horizontally away
from the ramp. The net force acting on the car is large enough to make the car to accelerate down the ramp. At 30 cm the speed was 0.97 and at 40cm the speed 1.49, the speed increased by 0.52. This shows that there was a positive correlation between the height and the
Speed.
Evaluation
What I did well…..
In my experiment what went well was making sure the trolley was
started on the same spot on the ramp ready for each run. Also the
timing of the experiment was very good because as soon as the trolley
had left the ramp completely the timing was stopped then.
What went wrong?
In my group the clamp didn’t seem strong enough to hold the ramp, which meant that the ramp kept falling causing the experiment to stop to fix it, also when the car came to the end of the ramp it smashed into the table causing a loud bang. Next time I’ll put something there to stop it. I should have also made sure that the to keep the experiment a fair test to make sure the timing started as soon as the trolley had been let go off because sometimes the timing started before the trolley had been let go of.
Evaluation of my conclusion
I think that my experiment went well over all and was reliable as I repeated it 2 times to get an average, also I made sure everything was accurate and my graph showed this because as I accepted there was a positive trend which lead to a solid conclusion. There is an increasing GPE as the height increases and therefore led to an increase in kinetic energy and speed. The trolley is at is at its highest point of 60cm it has the highest GPE then as the trolley drops to a lower level it loses GPE. However it gains the same amount of kinetic energy. If the kinetic energy increases it means the speed is increasing because the mass of the trolley went hence taking less time to reach to the bottom of the ramp.