Average Power of Elevator Motor Calculation

What is the average power of the elevator motor during the time interval when it accelerates?

Pave = hp

What is the motor power when the elevator moves at its cruising speed?

Pcruising = hp

Answer:

For the average power of the elevator motor during acceleration:

Pave = 18.33 hp

For the motor power when the elevator moves at its cruising speed:

Pcruising = 0 hp

To calculate the average power of the elevator motor during acceleration, we need to find the work done by the motor and divide it by the time interval. The work done is the sum of the work required to overcome the weight of the elevator and the work required to accelerate it.

Initially, the elevator is at rest, so the net force acting on it is the force required to overcome its weight, which is 4900 N. To accelerate the elevator, an additional force of 875 N is required. The distance traveled during acceleration is 7.875 m.

The work done by the motor can be calculated using the formula: Work = Force × Distance. By calculating the work done and dividing it by the time interval of 3.00 s, we get the average power of the elevator motor as 18.33 hp.

When the elevator reaches its cruising speed of 1.75 m/s, it moves at a constant velocity with no net force acting on it. Therefore, the motor power required to maintain the cruising speed is zero, resulting in a power of 0 hp.

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