What is the different between input motor elec.power and the output power,meaning?

Question

please explain in formulas.

Answer 1

the input power is measured in electricity- amps, and volts, and the output power of a motor is measured in the work that it does- horsepower and rpms.

An electric motor takes electricity and converts the energy into the work that it does- pumping water, turning a fan, opening a door, pulling an elevator up and down, etc.

Answer 2

The "difference between" input power and output power is the loss of power within the motor.
The (output power divided by the input power) times 100 equals the percent efficiency of the motor.
In order to do these direct comparisons the two powers need to be expressed in the same units. In the case of electric motors, the shaft mechanical horsepower and the connected input power could both be expressed as Kilowatts.
Mechanical HP = kW (0.754)

Answer 3

Input electric power is the power you provide to the instrument. you won't get 100% output beacuse of mechanical parts rubbing against each other and they would generate and lose energy in the form of heat because of Frictional force that acts between the parts. The power then coming out of the instrument is regarded as output power.

Answer 4

The difference between input power and output power is Efficiency and is expressed in %. Output Watts/ input watts =% efficiency. If a machine consumes 100 watts per hour and produces 50 watts per hour of useful work it would be considered to have 50% efficiency.

Answer 5

Efficiency. No motor, or any other energy using device, are 100% efficient. There will ALWAYS be a loss, due to heat generation, noise, vibration, etc.