NEETPhysicsWork Energy and PowerMCQ+4 / −1
An electric lift with a maximum load of 2000 kg (lift + passengers) is moving up with a constant speed of 1.5 ms1. The frictional force opposing the motion is 3000 N. The minimum power delivered by the motor to the lift in watts is : (g = 10 ms2)
- A23000
- B20000
- C34500
- D23500
View written solutionFree
Correct answer: C
Fup = 2000 g + 3000
= 23000 N
Minimum power Pmin = $\overrightarrow F $ . $\overrightarrow v $
Pmin = Fv = 23000 $\times$ ${3 \over 2}$
= 34500 W
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