Which of the following methods may be adopted to reduce the effects of armature reaction?

If excitation of a synchronous motor running with a constant load is decreased from its normal value, ignoring effects of armature reaction, it leads to

A

increase in both armature current and power factor angle

B

increase in back e.m.f. but decrease in armature current

C

increase in both armature current and power factor which is lagging

D

increase in torque angle but decrease in back e.m.f.

Rabindranath Tagore's 'Jana Gana Mana' has been adopted as India's National Anthem. How many stanzas of the said song were adopted?

A

Third and Fourth stanza

B

The whole song

C

First and Second stanzav

D

Only the first stanza

Which treaty aims to reduce greenhouse gas emissions globally and was adopted in 2015?

A

Kyoto Protocol

B

Paris Agreement

C

Montreal Protocol

D

Geneva Convention

The demagnetizing component of armature reaction in a D.C. generator

A

Reduces generator e.m.f.

B

Increases armature speed

C

Reduces interpoles flux density

D

Results in sparking trouble

In D.C. machines, ir order to prevent excessive distortion of field form by the armature reaction, the field mmf must be made

A

equal to that of armature mmf

B

less in comparison with the armature mmf

C

large in comparison with the armature mmf

D

none of the above

Armature reaction of an unsaturated D.C. machine is

A

Cross-magnetizing

B

Demagnetizing

C

Magnetizing

D

None of above

In a separately excited generator supplying rated load the armature reaction:

A

Is always present

B

Is always absent

C

May be sometimes present

D

None of the above

Armature reaction in a generator results in

A

Demagnetization of leading pole tip and magnetization of trailing pole tip

B

Demagnetization of trailing pole tip and magnetization of leading pole tip

C

Demagnetizing the center of all poles

D

Magnetizing the center of all poles

As a result of armature reaction, the reduction in the total mutual air gap flux in a D.C. generator is approximately

A

40 percent

B

25 percent

C

10 percent

D

5 percent

Many companies now have employee assistance programs that enable employees, free of charge, to improve their physical fitness, reduce stress, and learn ways to stop smoking. These programs increase worker productivity, reduce absenteeism and lessen insura

A

Physical fitness programs are often the most popular services offered to employees.

B

Studies have shown that training in stress, management is not effective for many people.

C

Regular exercise reduces people's risk of heart disease and provides them with increased energy

D

Employee assistance programs require companies to hire people to supervise the various programs offered.

Which of the following methods may be adopted to reduce the effects of armature reaction?

Related Questions