You connect two similar heating coils in series on a constant-voltage line.When you later connect them in parallel to the same line,the heat developed per minute,compared with the former rate,is approximately
A)the same.
B)twice as great.
C)one-half as much.
D)four times as great.
E)one-fourth as much.

Question

Quizplus · Accepted Answer

When two identical heating coils are connected in parallel instead of in series, the total resistance of the circuit decreases, leading to an increase in the total current drawn from the power source. Since the power (and thus the heat developed per minute) is proportional to the square of the current (P = I^2R), and the current in the parallel connection is higher for each coil, the total power consumed (and thus heat developed) by the two coils in parallel is four times greater than when they are connected in series.

You Connect Two Similar Heating Coils in Series on a Constant-Voltage