Contents
Key Stage 4
Meaning
Electrical power is the rate of electrical energy transfer in an component.
About Electrical Power
- The SI Units of electrical power are Watts.
- Electrical power is the work done by an electrical current per unit time.
Equations
Equation 1
NB: You must remember this equation.
Power = (Energy Transferred)/(time)
\(P=\frac{E}{t}\)
Where\[P\] = Electrical Power.
\(E\) = Electrical Energy Transferred or Work Done by an electrical current.
\(t\) = The time over which energy is transferred.
Equation 2
NB: You must remember this equation.
Power = (Current) x (Potential Difference)
\(P=IV\)
Where\[P\] = Electrical Power.
\(I\) = Electrical Current through a component.
\(V\) = Potential Difference across the component.
Equation 3
NB: You must remember this equation.
Power = (Current)2 x (Resistance)
\(P=I^2R\)
Where\[P\] = Electrical Power.
\(I\) = Electrical Current through a component.
\(R\) = The resistance of the component.
Equation 4
NB: You must remember this equation.
Power = (Current) x (Potential Difference)
\(P=\frac{V^2}{R}\)
Where\[P\] = Electrical Power.
\(V\) = Potential Difference across the component.
\(R\) = The resistance of the component.