For the following questions answer them individually
The purpose of using dummy coil inDC machine is to
An inductor with a ferromagnetic core is supplied from a sinusoidal voltage source with frequency 'f'. The current drawn by the inductor will be
For a 6-pole DC machine with wave wound armature, the number of brushes required is
Function of interpoles in a DC machine is to
The commutator segments of DC machine are made of
Which one of the following is a speed control method of three phase squirrel cage induction motor?
In the circuit as shown, voltage measured between A, B, is found to be 70 V. Value of M is
Two coupled coills, connected in a series have and equivalent inductance of 16 mH or 8 mH depending on the connection. The mutual inductance between the coil is
Which one of the following is a valid value of coefficien of coupling between two inductors?