Elastic Bands The Cart Travels example essay topic

Planning Introduction For this piece of coursework I have been set a task to find what factors effect the distance a wooden block travels when projected over a surface. Each time I do this I have been asked to change a different variable. There was a wealth of different variables I could have chosen but for this particular experiment I have decided that I will change the weight of the block each time I fire it. This will involve firing the cart a certain number of times but each time adding some more weight. For my second variable I will change I have decided on changing the amount of elastic bands used to fire the cart.

This will involve each time of firing the cart adding one more elastic band to wherever the other bands used previously had been attached to. To carry this experiment out I will have to take a few precautions. Firstly I will have to make sure the chair that I will have the elastic bands attached to as my firing platform is securely attached and balanced on the table to make sure there is no risk of it falling on anyone or onto anything valuable or dangerous. Also I must make sure that when I fire my cart across the table there is no risk of it hitting anyone or once again anything. There is also a Few more things I must do before starting my experiment. Firstly I will carry out a preliminary experiment this is to test everything is working fine and also to see what works and what doesn't and to obtain a good method of firing the cart.

Finally to round the test off perfectly I must make sure it is a fair test. There are numerous ways I can do this. Firstly I must make sure that I only change one variable each time. Secondly I must make sure I use the same cart each time and I must ensure that I use the same apparatus each time even the same elastic bands. Preliminary Experiment During my preliminary experiment I tried many different methods of acquiring the data, firing the cart and types of apparatus used to fire the cart.

The purpose of this was to find the easiest, fairest and most efficient way of performing the experiment. Also this preliminary experiment has aided my opinions for my predictions. Method I have now carried out my preliminary experiment I have discovered the most efficient method of firing my cart which is easy and most of all fair. To fire the cart I will every time use the same standard desk to fire it across. For my firing platform I have decided on firing it from some elastic bands which will be attached to a run of the mill lab stool. Along the side of the desk I will place two one-metre rulers to get a measurement from when the cart stops.

Each time I fire the cart I will make sure that each time I pull it back to the begging of the ruler attached to the desk to give every go the same force and make it fair. Once the cart stops to measure it each time I will take the measurement from the most prominent point of the cart. To acquire the data for every weight or every amount of elastic bands I will take the reading three times and then average it out. This will make my data a lot more accurate and exact. Diagram This is an example of the stool I used Predictions For this experiment I am changing two different variables but only one at a time.

Firstly the amount of weight exerted on the cart. Each time I am going to add a ten-gram weight to the cart attached by selotape. During the rest of this write-up I will call this experiment A. Secondly I will change the amount of rubber bands I use each time adding one more onto the firing platform every time I fire it. I will call this experiment B. My prediction for experiment A is that as the weight of the cart goes up the distance that the cart travels will be less. This is due to the force acting against the car each time getting less and less equal.

Meaning the car will get slower and slower. My prediction for experiment B however is completely different. I predict that as you increase the number of elastic bands on the firing platform the cart will travel further. This is due to the amount of force firing the cart increasing every time giving the cart greater velocity causing it to travel further each time. List of apparatus o Metre ruler o Selotape o Wooden cart o Stool o Elastic bands o 10 g weights Analysing What I have found I have found many different things from this experiment. Firstly I have proved my first prediction for experiment that by adding more weight to the cart it will travel less and less as the weight goes up.

This is shown firstly in my graph for this experiment as the numbers go down and secondly in my table where the numbers get less and less. This is due to the fact that adding more weight will increase the friction and with more friction over a surface the slower something will travel over it giving the cart less acceleration meaning it will travel less. Secondly I have proved my second prediction for experiment B that with more elastic bands the cart travels further. Once again this is shown in my graph and in my results table as the numbers get bigger. This is in accordance with Newton's 2nd law, which states 'If a force acts on a body it causes the body to change its motion. ' So by adding more elastic bands you are causing the cart to change it's motion and travel further.

What I have observed from the graphs and data tables From the graphs and tables I have noticed a few patterns and coincidences. Firstly I have noticed that in the graph and data table for experiment A as the numbers get smaller they start to even out. This is due to the forces acting against the block becoming more equal which contributes towards and eventual equilibrium. Secondly I have noticed that in experiment B the numbers on the data table start off quite close to each other then as you add more bands the numbers go up. This is due to the force of the elastic bands going up firstly by doubling then by trebling and so on so each time the force becomes so much more. Evaluating To conclude this experiment I have found that I did not obtain any out of place or peculiar data from either experiment.

Also I think the quality of the data I have taken has been on the whole very good. There are a few things that maybe In a perfect world I could have done to improve this experiment. For example I could have measured each fire of the cart ten times each to obtain some very precise averages, I could have also maybe measured everything to the nearest micro metre to make the results obtained even more precise. To round the experiment off I think that it was a success and that I have taken some proper data that fits with the patterns of the graphs.