Question

A coil in the heater consumes power P. If it is cut into halves and joined in parallel, what power will it consume?

• A. $P^2$
• B. 2P
• C. P/2
• D. 4P

Answer 1

The correct option is D 4P

If a wire is cut into half the new resistance R’ = R/2

If both are connected in parallel equivalent resistance is $R_{eq}=\frac{R^{\prime }}{n}=$ R/4.

New power:
P' = $\frac{V^2}{Req}$
= $\frac{4V^2}{R}$
P’= 4P