Question

A non-inductive load takes a current of 15A at 125V. An inductor is then connected in series in order that the same current shall be supplied from 240V, 50Hz mains. Ignore the resistance of the inductor and calculate the inductance of the inductor

Answer 1

The inductance of the inductor is 0.051H

Step-by-step explanation:

From Ohm's law;

V = IR .................. 1

The inductor has its internal resistance referred to as the inductive reactance, X
`_(L)`, which is the resistance to the flow of current through the inductor.

From equation 1;

V = IX
`_(L)`

X
`_(L)` =
`(V)/(I)` ................ 2

Given that; V = 240V, f = 50Hz,
`\pi` =
`(22)/(7)`, I = 15A, so that;

From equation 2,

X
`_(L)`=
`(240)/(15)`

= 16Ω

To determine the inductance of the inductor,

X
`_(L)` = 2
`\pi`fL

L =
`(X_(L) )/(2 \pi f)`

=
`(16)/(2*(22)/(7)*50 )`

= 0.05091

The inductance of the inductor is 0.051H.