Physics Essay The Conservation of Energy
Uploaded by ihatesuchin on Jul 05, 2004
Since the beginning of time, energy has pervaded our earth. These days we rely on it to advance in our technological developments. We also need energy for a variety of other things such as: to keep our bodies alive and healthy, to run our machines and other technical devices, we also rely on energy to keep warm in winter and cool in summer. Energy is the ability to do work. People and other things can run out of energy (e.g. a marathon runner) in which case they can no longer have the ability to do work. In a mechanical situation, if a machine has energy it has the ability to apply a force to another body. There are many different forms of energy and there are many different places by which energy can be gathered. Forms of energy include: Potential energy, kinetic energy, gravitational potential energy, elastic potential energy and there are many more. Energy can be gathered in many ways using our natural recourses from the environment, for example: solar energy (from the sun) and hydroelectricity (where electricity is gathered by rushing water)
Hydroelectricity is when electricity is generated by rotating coils of wire (rotors) between the poles of a magnet. The rotors are turned by rushing water falling over them. In a hydroelectric plant, water in usually stored in a damn. As the water falls down and rushes over the vanes connected to the rotors it looses gravitational potential energy and gains kinetic energy. As the metal wire rotates around the magnet it generates electricity which is then sent along power lines to all areas of the city or town.
Here is a description of the transformation of energy as a pole-vaulter completes a jump. Firstly, when the pole-vaulter runs forward the muscles in the legs are doing work as a result of energy to push him/her forward. As the pole digs into the ground and stops, the forward motion of the runner causes the pole to bend, giving it elastic potential energy. If the pole-vaulter were to let go of the pole at this point, the pole release upwards rapidly. As he/she jumps off the ground, it slowly releases the elastic potential energy of the pole and transforms it into kinetic energy, forcing the pole-vaulter upward and forward. If he/she jumps too early, there would not be enough elastic potential energy created to force him/her over the...