Question

An electric motor of power 1000 W, operates at 250 V. Calculate the inductive resistance of the motor and current flowing through it.

Answer 1

P = 1000 W; p.d. = 250 V; R = ?; I = ?

(i) \[\text{P} =\frac{\text{V}^{2}}{\text{R}}\]

\[\therefore \text{R}=\frac{\text{V}^{2}}{\text{P}}\]

\[= \frac{250 \times 250}{1000}\]

= 62.5 Ω 

(ii) \[\text{R} = \frac{\text{V}}{\text{I}}\]

\[\therefore \text{I} = \frac{\text{V}}{\text{R}}\]

\[= \frac{250}{62.5}\]

= 4 A