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2 years ago

4

The elevator of a large building is to raise a net mass of 400 kg at a constant speed of 12 m/s using an electric motor. minimum

power rating of the motor should be

2 answers:

S_A_V [24]2 years ago

4 0

Answer:

$P=47.040 \ kW$

Explanation:

In the question given things are:

Total mass of elevator, $m=400\ kg$ .

It is also given that it moves with constant speed, $v=12\ m/s$ .

So, power for object moving in constant velocity is given as.

$P=m \times g \times v$ .

Putting all values in above equation.

$P=400\times 9.8 \times 12=47040 \ W=47.040 \ kW$ .

Hence, it is the required solution.

azamat2 years ago

3 0

P =Force*velocity
=mass*acceleration due to gravity*velocity
=(400kg)(9.81m/s²)(12m/s)
=47088W or 4.7*10⁴W

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