The Energy The definition of energy in physical way: Every soma has the ability to alter other somas’ position: to heat them or increase their speed. (This quality makes us able to produce solar cells) One of the somas’ properties is their abilities of interaction and alteration. The ability of alternation is typified by a quantum: the energy. types of energy: - kinetic energy                          - internal energy                          - potential energy The energy in physics is a scalar quantity typifies closed systems, which is constant in every transform in time.

The energy in physics is a scalar quantity typifies closed systems, which is constant in every transform in time.

The conversation of energy “It does not appear, but transform”-> during the interaction the more the one participant energy increases, the more the other participant energy decreases.

The power Typify the speed of the transforms. Mark: P-> speed=>

P= dE/dt = alteration/ elapsed time

Its measure is Watt (1000W= 1 kW, 1000000W= 1MW). 1 W means: 1 J alteration done in 1 s. 1W= 1 J/s
For example a power station’s power means, how much energy it generate in a unit of time.

The efficacy It typifies the thrift of the process. It shows the rate of the beneficial invested energy and the total energy. It is a rate that is why it doesn’t have measure.
n=DEn /DEö       d=delta-> means transfiguration.

The beneficial changing of energy is always than the total changing of energy that is why the efficacy can be 100% only in idealized case.
n max.1. (n- the mark of efficacy)

We are going to see efficacy in power stations. It is worthwhile to run a power station if it generates more energy than it needs for the work. That is why pays to build a nuclear power plan; it generates much energy with small investment.

Curious thingsThe bill for electricity must be paid by right of consumerism. It shows how much energy chop existence in a unit of time. This quantum measured in kilowatt-hour. From P= DE/Dt=>DE=PDt=> By this the measure of kwh can be constituted that is equal to the energy chop that is procreated in one hour by a one-kW-power apparatus.

 Transformers: the way of the electric energy from the power plant to our house.

 The photoelectric phenomenon: Electron secession from metal affected by light is called photo effect.

 for ThinkQuest | may.06 Competition ©The Lucchese Team (1522)