Kinetic energy Essay Example

Kinetic energy Paper To investigate how a height of a ramp affects the speed of a trolley which goes down it? Hypothesis: Potential energy Is energy in waiting, waiting to be converted to kinetic energy or the maximum energy reclaimable from a system e. g. the trolley at the top of the ramp has the most potential energy and can be converted into kinetic energy as it is rolling down the ramp. Kinetic energy -relates to the movement, of an object. Acceleration means getting faster, Acceleration = change in velocity (m/s)/ time taken(s). E. g. an acceleration of 2 (m/s)2 means that the velocity increases by 2 m/s every second. Mass mass is how heavy an object is, it is measured in Kg. Gravity gravity is a force which pulls down objects to the ground when they are in mid air, if the objects are allowed to fall, they will accelerate downwards. Friction is the force that tries to stop an object moving and which would have an affect on reducing the maximum Kinetic energy an object has. (I got this information from a Longman physics GCSE book) So as the trolley/car rolls down the ramp its potential energy is converted into Kinetic energy as the trolley moves. When the law of conservation of energy is applied. Preliminary work: Before starting the experiments I looked at all the apparatus I will use and investigated:   How high should the ramp be? I put the ramp on a flat surface and measured different heights initially I wanted to use a height of 20 cm but it was too high, and it was difficult to work out the speed of the trolley/car. This is because we reacted too slow as the car was traveling too fast. We will write a custom essay sample on Kinetic energy specifically for you for only $16.38 $13.9/page Order now We will write a custom essay sample on Kinetic energy specifically for you FOR ONLY $16.38 $13.9/page Hire Writer We will write a custom essay sample on Kinetic energy specifically for you FOR ONLY $16.38 $13.9/page Hire Writer At the end I used the heights ranging from 7cm 17 cm and the height of the ramp increase 2cm each time by using books as a height for the ramp, then I decided to use 5 different height; 7cm, 9cm, 11cm, 15 cm, and 17 cm. I then repeated the experiment three times to make sure my results are accurate and reliable.   What length should the ramp be? I was given an 1. 5 meter wooden plank to use as a ramp, but it was difficult to accurately time the traveling car as it went down the ramp this caused inaccurate results, so I marked a length of 1meter on the ramp, which made it easier to record my results Prediction: I predict that as the height of the ramp increases, the speed of the trolley/car will increase. The time taken for the trolley/car to move from the top to the bottom of the ramp will decrease as the steepness increases. When you put the car at the top of the ramp and let go gravity will force it down, its Potential energy decreases and its kinetic energy increases, its loss in potential energy equals it gain in kinetic energy. So PE=KE due to the law of conservation in energy. We can use these equations to work out how fast and object drops until it hits the ground (speed): PE= mgh, where m -mass, g- acceleration due to gravity, and h- height. Kinetic energy = 1/2 (mass) x (velocity)2, 1/2 mv2 =mgh or v2 =2gh (when I remove the constants, H v2 look below) KE= 1/2 mv2 ,where m-mass of the object, and v-is the speed. As you let go of the trolley/car, the potential energy will convert to kinetic energy PE=KE H v2 This graph shows that the height is Proportional to the speed2 of the trolley/car. PE=KE, in theory this is true but when letting the trolley/car go down the ramp some of the energy is lost in heat and friction. This graph shows that as the height increases so does the speed. Method: Apparatus: A wooden plank (ramp), books (used as height of ramp), trolley/car, and a stop watch. 1. I will first set up the experiment as the diagram above 2. Make sure all surfaces are smooth, and make the experiment as fair as possible (environment, trolley wheels, etc). 3. Make a height for the ramp by using books. 4. Put the car at the top of the ramp. Measure a distance a 1meter length on the ramp so when you let go of the trolley/car you will stat the stop watch as soon as it starts a meter and ends a meter as the diagram below 5. Do the experiment for six different sizes. 6. Repeat the experiment three times. Here are the measurements I used; 7cm, 9cm, 11cm, 13cm, 15cm, 17cm, 27cm, 37cm, 47cm, and 57cm. Safety:   Make sure that the area we work around is safe for the students and the experiment. Make sure nobody can or will get in the way of the trolley/car. Fair tests; I will make this experiment fair by: I will make sure that the environment is normal (not windy) e. g. if there is wind while we do our experiments the windy can act as an extra force to the trolley/car or it can act as a resistance and slow down the speed of the trolley. I will make sure that the ramps are smooth and no damage is or will be made on them. Make sure I use same trolley at all times, different trolleys may weigh different this to will change the speed the trolley/car. Make sure I always have the same length of ramp. Results: Here are the results for my experiment: Height Distance Time (sec) 1s 2nd 3rd Average time (sec) 7. There are three columns in the time section; this is because I have repeated my experiment three times. Using the formula I can work out the speed of the trolley/car: Speed = distance/ time, from the results above I have drawn another table: Height Speed (m/s) Speed2 (m/s)rom these results I can now plot two graphs that I expect to see as speed height, and speed height.