A 100 Ω resistor is connected to a 220 V, 50 Hz ac supply.
Question:

A 100 Ω resistor is connected to a 220 V, 50 Hz ac supply.

(a) What is the rms value of current in the circuit?

(b) What is the net power consumed over a full cycle?

Solution:

Resistance of the resistor, = 100 Ω

Supply voltage, V = 220 V

Frequency, ν = 50 Hz

(a) The rms value of current in the circuit is given as:

$I=\frac{V}{R}$

$=\frac{220}{100}=2.20 \mathrm{~A}$

(b) The net power consumed over a full cycle is given as:

P = VI

= 220 × 2.2 = 484 W