Question

The input power to a 3-phase, induction motor is 15KW. If the output torque is 88Nm at a speed of 1450 r.p.m., calculate the efficiency of the motor.

Answer 1

To calculate the efficiency of the motor, use the formula Efficiency = (Output Power / Input Power) × 100%. Convert the output torque to power using the formula Power = Torque × Angular Speed. Calculate the efficiency by dividing the output power by the input power and multiplying by 100%.

Step-by-step explanation:

To calculate the efficiency of the motor, we can use the formula:

Efficiency = (Output Power / Input Power) × 100%

First, let's convert the output torque to power. We know that Power = Torque × Angular Speed. We are given the torque as 88 Nm and the speed as 1450 rpm. We convert the speed to rad/s by multiplying by 2π and dividing by 60. So, the speed is 151.91 rad/s. Now, we can calculate the output power as (88 Nm) × (151.91 rad/s) = 13,423.28 W.

Next, we can calculate the efficiency using the formula:

Efficiency = (13,423.28 W / 15,000 W) × 100% = 89.49%