Electrical Machines Objective Questions – Set 2

Direction of the current in the compensating winding is________ to the direction of current in the armature conductors?

The size of inter pole are small as compared to main poles. What is the reason?

In DC machines internal characteristics are plotted between

In DC machine torque depends on which of the following?

What is/are the necessary conditions for voltage build up in self excited generator?

The effect of ------------------ on main field flux is armature reaction?

Series field consists of--------number of turns and ---------- conductors respectively

In DC machine shape of armature MMF wave is?

Flux density under leading pole tips in case of generator will

Brushes are always placed on--------------- , in order to achieve sparkles commutation?

Which of the following is/are the methods to reduce the armature reaction and its effects?

Flux density under trailing pole tips in case of generator will

Cross magnetization effects which of the following?

Find the reactance voltage when current is changed from -2A to 2A in 4 sec and self inductance is 1H?

Shunt field of DC generators consists of--------number of turns and ---------- conductors respectively

In DC machines shape of net flux density is?

Series generators are used in which of the following applications?

No load saturation characteristics are plotted between

Which of the following statements is/are correct ?

Armature flux is.............with respect to main field flux or main field poles?

Which of the following generators are used in arc welding?

Compensating winding is placed in the

Which of the following is/are the advantages of carbon brush over the copper brush?

For a dc machine shunt resistance and armature resistance values are

Which of the following is/are effects of armature reaction?

Demagnetization effects which of the following?

A 4 pole lap wound dc generator has 4 brushes, if one of the brush is damaged, what will be the change in V, I and P ratings

In DC machine shape of main field flux distribution is?

The functions of inter poles are

Dummy coils are used for