Basic Electrical Engineering: SI Units

Showing posts with label SI Units. Show all posts

Sunday, 6 August 2017

Power

Power is the rate of doing work. Inotherwords power is the work done per unit time.

The unit of power is joules/sec or watts.

Work done

Power ___________

Time

Power P = VI watts

Where

V = Voltage

I = Current

Symbol = P

Si Unit = Watts

Symbol = I

Si Unit = ampere

Ampere = (A)

Power

The dimension of power is energy divided by Time.

Symbol = P

Si Unit = Watts

Watt symbol = W

1 Watt = 1 Joule per second

Work

Common symbol = W

SI Unit = Joule (J)

Unit of energy = Joules

1 Joule (J) is the MKS unit of energy, equal to the force of one Newton acting through one meter