Electrical Machines Objective Questions – Set 2

In DC machines shape of net flux density is?

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

In DC machine torque depends on which of the following?

Series generators are used in which of the following applications?

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

For a dc machine shunt resistance and armature resistance values are

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

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

Flux density under trailing pole tips in case of generator will

Which of the following generators are used in arc welding?

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

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

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

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

Flux density under leading pole tips in case of generator will

No load saturation characteristics are plotted between

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

In DC machines internal characteristics are plotted between

Dummy coils are used for

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

Compensating winding is placed in the

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?

In DC machine shape of armature MMF wave is?

Cross magnetization effects which of the following?

Which of the following statements is/are correct ?

The functions of inter poles are

Demagnetization effects which of the following?

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

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