# simple math problem on electrical motor

#### HoopHoop

Joined Aug 22, 2016
24
if a 3 phase induction motor of 5 hp has speed of 1430 at rated load then what is its speed at 50% load?

thanks.

#### HoopHoop

Joined Aug 22, 2016
24
thanks but that didnt help.

#### Alec_t

Joined Sep 17, 2013
10,267
What is the synchronous speed of the motor?

Joined Jul 18, 2013
18,863
if a 3 phase induction motor of 5 hp has speed of 1430 at rated load then what is its speed at 50% load?
.
That is never going to be the same for each motor, individual characteristics of the motor, stator/rotor etc, come into play.
The example motor in the question would be a 50hz motor.
Max.

#### Kermit2

Joined Feb 5, 2010
4,158
Figure out the synchronous speed of the motor. Assume the line is 50 hz.

It is an induction motor. Induction motors produce ZERO torque at synchronous speed.

Yours produces 100% of rated torque at 1430 rpm.

Slip is a ratio of two numbers.

A ratio is the division of one number by another such that the mathematical answer is equal to or between 1 and zero.

If you can't get there from here then you are wasting time trying to learn this particular subject.