question of what the power of the electric current is not the easiest.If you already have an absolutely precise, it is very difficult.But this is one of the basic concepts of both physics and other scientific disciplines related to electricity.In everyday life, we often have to use this concept.
Without going into a detailed clarification of what an electric current, and what is its nature, to understand the related processes we use the analogy of a stream.Water flows from the higher-located site down.For electrical current situation is the same as it flows from the point with a high potential to the low potential point.The magnitude of the potential difference is called the voltage, is denoted by the letter U and is measured in units called volts.
Let's go back again to the stream.When the flow of water from a height of nisin on the transfer of certain amount of it from one place to another.When a current flows occurs about the same thing: a certain amount of electricity is transferred from one place to another.To measure this process, there is the current term
These two concepts - voltage and current - act as the main characteristics of electrical current.
Water flowing from top to bottom, carries with it a certain energy.Getting such as a turbine blade, it will cause rotation of the latter and do some work.Similarly, an electric current can do work.This work is performed per second, and has the power of an electric current.Taking her by the letter P, and it is measured in watts.
Work performed at falling water is determined by its amount falling on the turbine blades, and the height from which it falls.The more water the greater the height from which it falls, the more work is performed.Similarly, the higher the voltage (the difference in height of water) and amperage (i.e., water), the more the work performed, and hence, the power of the electric current.
If you try to formalize this concept, everything can be expressed in a simple formula:
P = I * U,
where: P - power of electric current, in Watts;
I - current in amperes;
U - the voltage in volts.
This is the basic formula by which you can determine the power of an electric current.
However, the electric current flows are not somewhere in abstract terms, but in real circuits that have their own characteristics.In particular, the conductor is a resistance, and the voltage U and current I are linked in a chain where the constant current through the resistance Ohm's law.So that the power in the DC if necessary can be expressed in terms of resistance, or take into account the characteristics of the circuit in terms of power by the current and voltage, Ohm's law related.
Due to the fact that the circuit has a resistance, not all the energy used to perform useful work.Part of it is lost during the passage of the chain.Therefore, the incoming energy, ie,power source shall be greater than the power needed to perform a certain operation.Must fulfill the so-called energy balance - Power supplied by the source, it must be equal to the power consumed by the load and the power lost in a conductor of electric current.
about so you can get a general idea of what the power of an electric current, as defined, on which depends.
