What SI units are used to measure power?

1 Answer
Mar 28, 2014

The SI unit for power is the watt.

Explanation:

The watt (W) is the SI derived unit for power. It comes from the SI base units.

Velocity is the rate at which an object travels.

#v = "distance"/"time" = d/t#.

The units of velocity are metres per second (m/s).

Acceleration is the rate at which an object changes its velocity.

#a = v/t#.

The units of acceleration are metres per second squared (#"m·s"^"-2"#).

Force is any influence that tends to change the motion of an object. Force = mass × acceleration.

#f = ma#.

The newton (N) is the force needed to accelerate up a mass of 1 kg by #"1 m·s"^"-2"#.

#"1 N = 1 kg·m·s"^"-2"#

Work is the action of a force through a distance.

#w = f × d#.

The units of work are #"kg·m"^2"s"^"-2"# or #"N·m"#.

Energy is the ability to do work. It has the same units as work. The SI unit for energy is the joule (J). #"1 J = 1 N·m"#.

Power is the measure of how much energy or work is used per unit time.

#"Power" = "energy"/"time"#

The SI unit of power is joules per second (J/s) or Watts (W).

In summary,

#"1 W = 1 J/s = 1 N·m/s = 1 kg·m"^2·"s"^"-3"#