a) Equations for power

a) the equations P = VI, P = I²R, and P = V²/R

electrical power = the rate of electrical energy transfer

P = W/t

• power dissipated by a component (W) = energy transferred by the component (J) / time (s)

P = VI

• power dissipated by a component (W) = potential difference across the component (V) x current in the component (A)

P = I²R

• power dissipated by a component (W) = current in the component² (A²) x resistance of the component (Ω)

P = V²/R

• power dissipated by a component (W) = potential difference across the component² (V²) / resistance of the component (Ω)