Practical showing the conservation of Energy

Authors Avatar by aishaharjanihari (student)

Experiment to show the conservation of energy

Aim:

Trying to prove the conservation of energy (energy isn’t made or broken, it can only be transferred) by showing the change of gravitational potential energy transferred into kinetic energy.

Variables:

Independent variable (the ones that change): masses, GPE input.

Dependant variable (the ones we measure): height, distance, velocity and KE.

Prediction:

I think that the Kinetic Energy will be slightly less than the Gravitational Potential Energy input taking into account the counteract forces such as friction and the waste energy in the form of heat and sound.  But the velocity will increase as the mass of the falling object increases because mass and velocity are directly proportional this also suggests that more mass means more KE.  This is because when the mass of an object increases the more initial GPE it has, and as it falls GPE is converted into KE until a point where there is no more GPE, so the more initial GPE the more final KE.

Fair test (ensuring that the experiment is valid):

Keeping dependant variables the same, using the same distance, which the trolley travels- by making sure it goes in a straight line and height from which the weights drop.

Using the same trolley.

Keeping the same elevation, using the same shape and number of books under the ramp.

Plan:

Setting Up The Apparatus: First we have to compensate the runway for friction, by raising one side of the board so that the trolley will travel at a constant speed. But it has to be judged carefully as if we elevate the ramp too much it will make the trolley accelerate and this will cause experimental error. If we didn’t compensate for friction a) it will slow down and eventually stop due to friction, b)it will accelerate because the force of gravity is stronger than friction, compensating the runway balances out both forces.

Join now!

After that we attach a length of string to the trolley and tie it to the mass hanger. The length of the thread must be long enough for the mass hanger to hit the ground before the trolley reaches the end of the runway. Secondly we measure the height the mass will fall to be able to then calculate the GPE and if we had to check later on or repeat the experiment we would have to use the same height in order to keep it a fair test. Later we attach a length of ticker tape to the trolley ...

This is a preview of the whole essay