# Old City & Guilds Question

#### Blueday1886

Joined Jan 19, 2022
4
Hi, I have the following question from an old City & Guilds paper:
A resistive load rated at 65 W, 110 V is to be used on a 230 V, 50 Hz supply.
Calculate
(b) voltage drop needed across a pure inductor connected in series with the load
(c) inductance of this inductor
(d) phase angle of the circuit
(e) explain the advantage of this type of current limitation and give one practical example.
Could someone point me to any reading material on this please as I can only find items relating to MCBs and fuses.
Many thanks.

#### AlbertHall

Joined Jun 4, 2014
11,952
Search for RL circuits - wiki for example.

#### MrAl

Joined Jun 17, 2014
8,861
Hi, I have the following question from an old City & Guilds paper:
A resistive load rated at 65 W, 110 V is to be used on a 230 V, 50 Hz supply.
Calculate
(b) voltage drop needed across a pure inductor connected in series with the load
(c) inductance of this inductor
(d) phase angle of the circuit
(e) explain the advantage of this type of current limitation and give one practical example.
Could someone point me to any reading material on this please as I can only find items relating to MCBs and fuses.
Many thanks.
Do you understand how to use complex numbers to analyze AC circuits? if so this is going to be fairly simple for you.
So you will have to state what kind of analysis you have done in the past or what you think you can use to solve this.

#### RBR1317

Joined Nov 13, 2010
690
It might help to plot what you know about the problem on a phasor diagram. Note that these will be voltage phasors because the component currents are the same in a series circuit.

#### Blueday1886

Joined Jan 19, 2022
4

#### Blueday1886

Joined Jan 19, 2022
4