what we mean by electric power?

Question

how we generate it?

Answer 1

electric power is nothing but a form of energy which can be utlized in different ways.
it can be basically generated by using a dynamo ( cycle dynamo)
it consist of two permanent magnets and a iron/steel shaft/rod in between the magnets. the principle is ," whenever a conductor cuts the magnetic field a form of energy is proudced which can be collected by carbon brush and then utilized as per the requirement.

Answer 2

Most electric power is generated by very large steam engines, the heat for which comes from a nuclear reactor or a coal fire. Lesser amounts of steam are produced by burning petroleum or natural gas, and there is a small amount of electric power produced by diesel engines. There's only a small amount of hydroelectric power produced in the US because our mountains are mainly dry, though we import a fair amount of hydro power from Canada.

We obtain the tiniest proportion of our power from wind generators, and approximately zero percent from solar power, a figure that is not likely to increase.

Answer 3

electric power is most commonly produced as a by-product of hydro-electric dams.

it is created by falling water turning massive turbines which creates energy that is stored nearby. It is then redistributed to us.

Answer 4

In circuits

Electric power, like mechanical power, is represented by the letter P in electrical equations, and is measured in units called watts (symbol W), named after Scottish engineer James Watt. The term wattage is used colloquially to mean 'electric power in watts'.

In resistive circuits, instantaneous electrical power is calculated using Joule's Law, which is named after the British physicist James Joule, who first showed that electrical and mechanical energy were interchangeable.

P = I * V

where

P = power in watts
I = current in amperes
V = potential difference in volts

For example: 2 amperes * 12 volts = 24 watts.

Joule's law can be combined with Ohm's law to produce two more equations:

P = (I ^ 2) * R

and

P = (V ^ 2) / R

where

R = resistance in ohms.
For example:

(2 amperes)2 × 6 ohms = 24 watts

and

(12 volts)2 / 6 ohms = 24 watts.

In reactive circuits, energy storage elements such as inductance and capacitance may result in periodic reversals of the direction of energy flow. The portion of power flow that, averaged over a complete cycle of the AC waveform, results in net transfer of energy in one direction is known as real power. That portion of power flow due to stored energy, that returns to the source in each cycle, is known as reactive power.

The unit for reactive power is given the special name VAR, which stands for volt-amperes-reactive. In reactive circuits, the watt unit (symbol W) is generally reserved for the real power component. The vector sum of the real power and the reactive power is called the apparent power. Apparent power is conventionally expressed in volt-amperes (V·A) since it is the simple multiple of rms voltage and current.

Power triangleThe relationship between real power, reactive power and apparent power can be expressed by representing the quantities as vectors. Real power is represented as a horizontal vector and reactive power is represented as a vertical vector. The apparent power vector is the hypotenuse of a right triangle formed by connecting the real and reactive power vectors. This representation is often called the power triangle. Using the Pythagorean Theorem, the relationship among real, reactive and apparent power is:

(apparent power)^2 = (real power)^2 + (reactive power)^2

In space

Electrical power flows wherever electric and magnetic fields exist in the same place. The simplest example of this is in electrical circuits, as the preceding section showed. In the general case, however, the simple equation P = IV must be replaced by a more complex calculation, the integral of the vector cross-product of the electrical and magnetic fields over a specified area, thus:

P = Surface Integral [E * H .dA]

The result of this integral is a vector, since power has both magnitude and direction.