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PHYSICS

JAMB 2021 - Question 10

Physics 2021 JAMB Past Questions - Question 10: What is the correct formular for the efficiency of a device?

Choose the correct answers from the options given.

What is the correct formular for the efficiency of a device?

A: input/output

B: output/losses

C: losses/(output+losses) -1

D: . 1- (losses/(output+losses))

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Correct Answer

Explanation

The efficiency (\( \eta \)) of a device is typically calculated using the formula:

\[ \eta = \frac{\text{Useful energy output}}{\text{Total energy input}} \times 100\% \]

This formula gives the efficiency as a percentage, showing how much of the input energy is converted into useful output.