Question Detail
Question
A combination of three equal resistances in series is equivalent to 90 W. What is the equivalent power when they are connected in parallel?
Correct Answer
Option C is the correct answer.
Detailed Explanation
Power P ∝ 1/R. Series resistance is 3R. Parallel is R/3. The resistance decreases by factor of 9, so power increases by factor of 9 (9 × 90 = 810W)
Hint
The parallel combination has 1/9th the resistance of the series one.