Реферат на тему Forces And Weights Investigation Using Trolleys And
Работа добавлена на сайт bukvasha.net: 2015-06-23Поможем написать учебную работу
Если у вас возникли сложности с курсовой, контрольной, дипломной, рефератом, отчетом по практике, научно-исследовательской и любой другой работой - мы готовы помочь.
Forces And Weights Investigation Using Trolleys And Ticker-Tape Essay, Research Paper
Planning: To perform this experiment, we will work in pairs each taking a certain number of results and then putting them together. Setting up the apparatus will be one of the hardest parts of the experiment. The first thing we will do, is set our board a t an incline carefully adjusted so that no force will change the speed of our trolley, meaning once its going, it keeps going. This will be setup using a few books. After that is done, we will insert a pulley at the end of the table to make sure that the experiment works smoothly. Then, we will take a power adaptor to power our ticker timer dispenser. We will connect them using plugs and, when the time is right, power it to make it work. We will then cut a piece of thread approximately the length between the ground and the table, plus the length between the end of the table and the beginning of our board. To this string, we shall attach different weights as our experiment goes on. We will then cut some self-marking ticker timer paper and place in the ticker timer machine. Then, we shall attach the string to the trolley on the front, and the ticker timer paper at the back. We will then, be ready. Except for one thing, our safety. We have to make sure that we are safe in every way and that no harm could possibly come to us. We must be careful not to place our feet next to the falling weights and not to stick our fingers in the electric sockets. After we are sure that everything is safe, we will be able to begin. We will choose a weight, say 100 grams, we shall record that weight, and then we shall simultaneously turn on the electricity and let go of the trolley with the weights attached onto the end. Once the trolley has bounced back on the elastic band, we shall turn off the electricity and remove the ticker timer paper (t.t.p.) for further record. We then, shall change the weight and start anew. We shall place some new t.t.p. in the t.t.p. machine and recommence what we have just done. We shall repeat this procedure several times changing the weights, making sure that our safety come first. Obtaining evidence: We will make sure to record enough results to make an accurate and definite conclusion. We will keep a record of results by dividing our ticker timer paper in 1/10 of second strips that will stick on graph paper as a graph showing the increase (or decrease) in the speed of our trolley. This method of recording our results should be very clear as we will not be doing too much writing. If our results vary, or we lose our results then I will redo the experiment. We will have to make sure to record results in a safe way as our safety comes first. We will make sure not to get in the way if electric currents and our results will have to be analysed in a safe environment. The equipment we will use will record the results as accurately as is possible. It makes 50 dots per second and I don’t think that with our limited funds we could acquire a machine that is more accurate. Thus, our results, machine wise, will be of the utmost accuracy. It is human error that will ascertain failure in accuracy. Therefore, we will be as careful as possible to make sure that we do not impose an error into the experiment. Our results will be made over a very wide range. We will measure out 100, 200, 300, 400, and 500 grams in the weights to perform our experiments. This should ensure a wide range of results that will help our conclusion be accurate. To record our results, we will make graphs (as seen in evaluating evidence) of averagely 1/10 of a second in between all of our records. We cannot effectively make a table to show our results, a graph is the only real way, apart from writing about it. I will repeat some results if I am not satisfied with a certain one (or if I lose it). The main point I am trying to emphasise is that we will have to have enough results over a wide enough range to draw a firm and accurate conclusion. Safety is still an important key thing in this whole experiment but in the end, it is the results that count. Analysing evidence and drawing conclusions: From the graphs we saw that the heavier the weight attached to the end of the trolley, the faster it went, and thus the larger the graphs became. The four hundred gram graph speed went up to 165 when the 100 gram graph went up to 120. As we see from the acceleration, the trolley pulled by 100 grams went 122.22cm/s/s. The trolley pulled by the 200 grams went 130cm/s/s and the trolley pulled by the 400 grams went 168.75cm/s/s. This definitely shows an increase in the acceleration of the trolley. That is basically what we have discovered. We have displayed our results in the above charts. The patterns are quite distinguished, there is no mistaking, they are all on the rise. My conclusion is that, the more weight pushed, or pulled, on an object (for example the trolley), the more force exerted on the object in a certain direction. Therefore, if the string has more weight on the end, then a greater force will be pulling the trolley with little friction to stop. The force is important in a moving object but the friction is also of great importance. If the ground is rough, then it will move with less ease. If it is smooth, then the object will go further. The previous scientific knowledge I had was a very obvious one. I, obviously knew, that if a greater weight was added, then the trolley would go faster. This is common sense to practically everyone in this world today. Evaluating Evidence: This experiment was far from flawless. I made many (human) errors. On on of the graphs, I measured 7 dots out instead of 5. This was a mistake that I could have avoided if I simply had put more time into doing my graph. Also, I lost the first set of my t.t.ps. I had to redo them all, in about 5 minutes. I had to run to get my apparatus set up. Do the three experiments, then run to clean everything set up. This still made me receive good results, however, as the t.t.p. machine works perfectly if properly operated. My graphs were about as comprehensive as I could make them, which wasn’t very, and I got a little confused when I had to work out my acceleration and I probably have some inaccurate results in that area. Otherwise, everything went fine. There were, of course, minor glitches that didn’t really affect the actual turnout of the experiment. Like, for example, the fact that I ran out of pages in my book so I had to rip them out. This has nothing to do with the experiment, but in the end, affects really only the morale of the person doing the experiment. If that person is discouraged, then the outcome of the experiment may not be as good as the person won’t have set his/her heart into it.