⚡ Electrical Machines – Short Questions & Answers
01 What is an electrical machine?
An electrical machine is a device that converts electrical energy into mechanical energy, mechanical energy into electrical energy, or transfers electrical energy between circuits through electromagnetic induction.
02 What is the difference between an electrical motor and a generator?
An electrical motor converts electrical energy into mechanical energy, whereas a generator converts mechanical energy into electrical energy.
03 What is the working principle of a transformer?
A transformer works on the principle of mutual electromagnetic induction. A changing current in the primary winding produces changing magnetic flux, which induces an EMF in the secondary winding.
04 What is synchronous speed in an electrical machine?
Synchronous speed is the rotational speed of the magnetic field produced by the stator of an AC machine.
Where f = supply frequency (Hz), P = number of poles, and Ns = synchronous speed (RPM).
05 What is slip in an induction motor?
Slip is the difference between synchronous speed and actual rotor speed, expressed as a fraction or percentage of synchronous speed.
Where Ns = synchronous speed and Nr = rotor speed.