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Work, Energy, and Power — Physics STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 SciencePhysicsWork, Energy, and Power3 Marks
Question
Why is electrical power required at all when the elevator is descending? Why should there be a limit on the number of passengers in this case?
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Answer

When elevator is descending then it is not its free fall under gravity it descends with uniform speed. Power is required to decrease the velocity due to free fall. Power of motor or system of an elevator is constant and a limited or specified power can stop the speed of freely falling of passenger along with elevator.

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