EE-3 75 TO 100

The relationship between generated emf and applied voltage in case of dc generator is given as

• Eg = V + IaRa

• Eg = V – IaRa

• Eg = V

• none of these

In a d.c generator, the generated e.m.f is directly proportional to the ____________

• field current

• pole flux

• number of armature parallel paths

• number of dummy coils

The series field of a short-shunt d.c generator is excited by ____________ currents.

• shunt

• armature

• load 

• external

The open circuit characteristics of a dc generator is the curve between

• V and Ia

• E and Ia

• E0 and If

• none of the above

The external characteristic of a dc generator is the curve between

• V and IL

• E and Ia

• E0 and Vf

• none of the above

The internal characteristic of a dc generator is the curve between

• V and Ia

• E and Ia

• E0 and Vf

• none of the above

Stray losses consist of ____________

• magnetic and mechanical losses

• magnetic and copper loss

• iron loss and copper loss

• mechanical and copper los

The commercial efficiency of a shunt generator is maximum when its variable loss equals ______ loss

• constant

• iron

• friction and windage

• none of the above

A dc motor can be looked upon as dc generator with the power flow

• reduced

• reversed

• increased

• modified

The induced emf of armature conductors of a dc motor is

• sinusoidal

• trapezoidal

• rectangular

• none of the above