2.0 Summary

Give three examples of evidence for the presence of energy (i.e. You can see it physically)

1. When a light turns on, it is evidence of the presence of both electrical energy, and light energy.

2. When an object (such as a power drill) is moving, that is evidence of kinetic energy, and in this example, also of electrical and mechanical energy,

The Law of Conservation of Energy states that energy can neither be created or destroyed. However, it can change its state. For example a ball sitting at the top of a hill has potential energy, but as soon as it starts rolling down the hill, the potential energy is converted into kinetic energy. The potential energy remains in the ball until right before it has stopped rolling. At this point the potential energy is at its minimum. But since the law of conservation states that energy can't be destroyed, the energy doesn't just disappear. It is transferred into kinetic energy which is now at its fullest potential. Mechanical energy is the sum of the potential and kinetic energy. Therefore, the mechanical energy remains constant, 

State the types of energy shown on this diagram and where it is being used.

The water that is stored in the dam: Potential Energy

The water that goes through the flood gate: Kinetic Energy

As the water rotates the blades: Kinetic Energy

As the generator converts the energy: Electrical Energy

In Greece scientists were puzzled over what caused heat, a group called atomists believed it had somethings to do with atoms, however other Greek groups did not believe in the existence of atoms so the idea was put aside. In the mid 1700's a scientist named Joseph Black that heat flowed through hot to cold things due to his experiment, he put a cold spoon into a hot cup and found the spoon to be cold after a while. He thought that an invisible liquid flowed through the objects, he called it the 'caloric fluid', this discovery became one of the main principles of thermodynamics. Thermodynamics is  the study or interrelationships between heat, work, and energy.

Count Rumford proved Joseph Black that his theory on caloric fluid was wrong. He noticed that when you make cannons, the heat that it was giving off was tremendous. He thought that if heat was fluid you would end up running out of it, however heat would continue as long as you kept making holes in the cannon. Scientists realized that they were different types of energy and that heat and mechanical energy converted from one to another.

Volta Pile, Alessandro Volta 

Scientist were perplexed by Newtons cradle because they didn't know how it worked. Then Gottfried Leibniz, a physicist, said that a living force is what caused the balls to move, he called this living force vis viva . He said that there were two types of living forces in the natural word. One being an object in motion that caused it to do work, called kinetic energy. The other one called gravitational potential energy, which was the objects ability to be able to do work because of it's position. The whole of energy of motion and position (kinetic and gravitational) is called mechanical energy.

Nuclear Energy is the potential energy stored within the nuclei of an atom. There are two ways for energy to be released in which you could join the nucleus of two atoms which is called nuclear fusion. You could also split the nucleus of an atom which is called nuclear fission.

Solar Energy is caused by a hydrogen-hydrogen nuclear fusion reaction which releases nuclear energy on to the earth called electromagnetic reaction which is then turned into other types of energy such as heat. The scientist thought that the sun got it's energy from burning itself, however the sun would have burnt out in five thousand years. Scientist soon discovered nuclear energy and discovered that it was a nuclear fusion that was happening on the sun.

Electrical energy is the work done by moving charges, also known as electricity. Italian physicist Alessandro Volta invented a machine (Volta Pile) , in the early 1800's, which was part of the first  battery. It consisted of metals that were stacked upon each other and a wet paper between each metal. It had a wire connected to the top end and the bottom which created a constant electrical current. The machine proved that there was a relationship between chemical an electrical energy, then the study of electricity began.