Electrica 2 - chapter 4

D.C generator is to convert mechanical energy into

• potential energy
• electrical energy
• mechanical energy
• none

This figure reprasents?

• d.c motor
• d.c generator
• a.c motor
• a.c generator

Fleming’s right hand rule is applicable to

• dc generator
• dc motor
• transformer
• all of the above

The sole purpose of a commutator in a dc generator is to

• increase output voltage
• duce sparking at brush
• provide smoother output
• onvert the induced ac into d

The yoke of a DC machine is made up of                 

• Silicon steel
• soft iron
• aluminium
• cast steel

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

This figure reprasents?

• d.c series generator
• d.c shunt generator
• d.c motor
• d.c compound generator

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

• field current
• pole flux
• mber of armature parallel pat
• 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