Wednesday, January 29, 2020

The efficiency of energy conservation Essay Example for Free

The efficiency of energy conservation Essay Safety In this experiments the staple that is fired has sharp ends to it and so it can be dangerous. So throughout this experiment I will wear goggles and work in an area away from others. Method 1) Set up the equipment as shown in the diagram on the first page. 2) Cut a 8cm of string 3) Attach the string to the weight holder (weight holder weighs 100g) 4) Attach the other end of the string to the elastic band. 5) Measure the extension of the elastic band and record it. 6) Get into the right position to record the height of the staple. 7) Cut the string and record the height to the nearest 5cm. 8) Repeat each test 3 times and then take an average of the height. 9) Repeat the same experiment using the next weight (200g). Obersavation and Recording To calculate the amount of elastic energy stored in the elastic band at different extension, I drew a graph based on the results shown below. The area under the graph is represented of the elastic energy stored at various extensions. From my graph, each 1cm   1cm square is represented ofThe elastic energy is an approximation. I have tried to be as accurate as possible whilst counting the squares. I found that the distance from the floor to the ceiling was 3. 32m and the distance the elastic band traveled from rest while attached to the clamp to the point where it hits the ceiling to be 2. 07m. From looking at the results we can see that the maximum height reached by the staple, the point where it hit the ceiling was when its extension was 10cm. From this I can calculate the amount of elastic energy stored in the band using my graph. I can also calculate the amount of energy transferred to the staple, ie the potential energy gained, by using the equation mgh. Evaluation In the experiment I was trying to measure the efficiency of the energy transfer for the staple fired into the air, by the elastic band. The energy conversion in the experiment is the transfer of elastic energy stored in the elastic band to potential energy gained by the staple after it has fired into the air. Elastic energy i Potential energy From looking at my results the general pattern is that an increase in extension increases the height of the staple that is fired. The graph I have produced, force extension graph also show this. The graph does not follow Hookes law, as the line is not straight. The values I collected for the elastic energy was 0. 170 J and energy converted into potential energy in the staple after it had been fired was 0. 041 J. The percentage efficiency for this energy transfer was 24. 1%. This means only a small amount of elastic energy was converted to potential energy and most of the energy had been lost. The reason for this could be due to the air resistance. I stretched the elastic at different lengths and observed how far the staple shot off as a result. At first the relationship between the extension and the distance was close, nearly the same. Then air friction could of decreased the distance traveled for a given stretch. This would mean that the staple would have gained less potential energy. Also this experiment involves the transformation of elastic energy to potential energy between the elastic and the staple. But when the elastic band is stretched and released this involve the transformation of elastic energy to kinetic energy so some energy could have been lost due to this kinetic energy. Another reason could be that when stretched, energy could of been lost as a form of heat. When the elastic band is stretched the rubber polymer chains become more orderly and H bonds form between these chains. This H bond formation is exothermic therefore the stretched elastic band will feel warm and heat will be lost. (Reversing this process (when unstretched), the polymer chains become disorderly, the H bonds break and as this is endothermic, heat is absorbed and the band feels cool. ) This heat energy lost will have an effect on the transfer of energy between the elastic band and the staple. To keep this experiment as accurate as possible I took 3 reading for each test and then I took an average. I used appropriate and reliable equipment and used them properly. When taking the results I will also draw the graph at the same time so if any chance an anomalous result does occurs I can go back and repeat the same test to get the right result. I also design the experiment so I would be as accurate as possible using the equipment from the lab. I thought that the experiment went well, the results that I got I thought was accurate and reliable. I thought that the experiment was well planned, reducing any factor that would lead to unreliable results. Show preview only The above preview is unformatted text This student written piece of work is one of many that can be found in our GCSE Electricity and Magnetism section.

Tuesday, January 21, 2020

I Intend to Pursue the Study of Medicine :: Medicine College Admissions Essays

Admissions Essay - I Intend to Pursue the Study of Medicine I walked off the school bus; it was a beautiful summer day. The sun was shining and the birds were singing, but inside my house it was dark, a cloud had moved over us. I slowly made my way to the door, expecting my mother to greet me but instead my sister opened the door, something was wrong, I knew instantly. When I walked in and there sat my three year-old little brother playing with his toys in the family room and my parents were sitting on the couch. I looked up at my mom, she had been crying. What is wrong I asked? He is sick my mom said, "Your baby brother is very sick". I just shrugged my shoulders and walked away, I had been sick before and I got better, so would he. I went upstairs to my room and made a get well card for him. It was made out of blue construction paper and had black writing on it, I finished it off with a panda bear sticker. Inside I had written how much I loved him and to get better real soon. I proudly presented it to my mother; she took one look at it and began to cry again. I climbed on to her lap and she said, "He won't get better, we have to take care of him the best that we can". He has diabetes she explained but my naïve eight year-old mind just did not know what diabetes was. I did not understand. Whenever I was sick I went to the doctor and he always made be better, but this time even the best doctor's hands were tied. It was this very day I knew what I wanted to do when I grew up...I wanted to make my little brother better, I wanted to be a doctor. Although this was this first time that being a physician crossed my mind. I was sure I was destined to become one. I have always felt a deep desire to help people whenever they needed it, and would stop and no end to help them. Through the many volunteering experiences and through various jobs, my decision was solidified. My first trials with medicine and dealing with the ill began when I was twelve years old.

Monday, January 13, 2020

High School Conformism Essay

Throughout majority of my high school life, I always questioned why things operated the way they did. Being forced to go to a place, or my parents could possibly go to jail. To be honest it sort of felt like a indoctrination. Going there I noticed everything was controlled and different social groups where created based on different peoples personalities. The irony of it all is that from a young age school seemed to indorse individuality, yet hypocritical policies such as school uniforms still took place later in the years. I questioned why there was so much conformity;why was everyone so worried about fitting in? While I can’t be the voice for every-ones’ reasoning behind peer pressure. I can give my own reason for occasionally feelings of peer pressure. The first 2 years of high school felt very much like a fight for my individuality. I’d find multiple ways to make myself feel as if I was different; for instance making modifications to my uniform. I also would follow subculture Stereotypes, although at the time I didn’t realize it was simple was pressure: The pressure to pull away from what I considered social emptiness. This was a phase thankfully, and thankfully I slowly I began to realize; I was essentially doing what other students where doing, but strangely for the opposite reasoning(to get away from conformism). I’d say its a great learning experience, and simply put. The best way to strive for individuality is not striving for individuality. When you force yourself to be different, weather it be following a subculture (beyond your own personal beliefs), or not liking a ideology without doing your own research. You’ll definitely fall into the ignorance of conformism. After coming to these conclusions, I decided to become more social; experiencing new things so I could have a opinion, rather than stagnate in ignorance. I’ve learned a lot in regards to life, but most importantly I learned a lot about myself. I can finally say that I am a individual. I believe high school has definitely had a impact on me, although I’m sure it wasn’t there intention to give me such enlightenment.