Question

A coil of inductance 0.50 H and resistance 100 Ω is connected to a 240 V, 50 Hz ac supply. 

(a) What is the maximum current in the coil? 

(b) What is the time lag between the voltage maximum and the current maximum?

Answer 1

Inductance of the inductor, L = 0.50 H 

Resistance of the resistor, R = 100 Ω 

Potential of the supply voltage, V = 240 V 

Frequency of the supply, ν = 50 Hz 

(a) Peak voltage is given as:

Angular frequency of the supply, ω = 2 πν 

= 2π × 50 = 100 π rad/s 

Maximum current in the circuit is given as:

Hence, the time lag between maximum voltage and maximum current is

Now, phase angle Φ is given by the relation,

Hence, the time lag between maximum voltage and maximum current is 3.2 ms.