Question

The resistance in the circuit is 10 $\Omega$. The operating voltage is fluctuating; the appliance in the circuit operates best at 4kW. What is the operating voltage?

• A. 100 V
• B. 150 V
• C. 200 V
• D. 250 V

Answer 1

The correct option is C

200 V

P = V $\times$ I,

We have, P =$\frac{V^2}{R}$

$\Rightarrow$ P $\times$ R = $V^2$​

$\Rightarrow$ $V^2$​​ = 4000 $\times$ 10

= 40000

$\Rightarrow$ V = $\sqrt{40000}$

= 200V