Physics for IGCSE & O level - Forces And Energy (Section 1 - No. 17)
In the formula, efficiency = (useful power output) / (total power input), which is the correct format?
Useful power input should be greater than total power input.
Total power input should be greater than useful power output.
Total power input and useful power output should be equal.
Total power output should be greater than useful power input.
توضیح
Total power input is always greater because some energy is lost.