Question

The electric circuit (above figure) in a clothes dryer contains two heaters X and Y in parallel. The above figure shows the circuit connected to a 230 V power supply. When both switches are closed, the current in X is 3.5 A. 

Analyse the circuit given above and answer the following questions: 

(i) Calculate the power developed in heater X. 

(ii) If the resistance of X is double that of Y calculate the current in heater Y.

Answer 1

P = VI

= 230 × 3.5 = 805 W

I ∝ 1/R, so half the resistance means double the current.

Therefore, current in Y = 7.0 A.