Electrical Engineering Mcqs

In a D.C. machine, the value of peripheral speed should not, normally, exceed___________?

(A) 10 m/s
(B) 20 m/s
(C) 30 m/s
(D) 40 m/s

Submitted By :Ali Uppal

The weight of copper of both armature and field windings decreases with __________ in number of poles?

(A) increase
(B) decrease
(C) either of the above
(D) none of the above

Submitted By :Ali Uppal

A practical formula for determining the thickness of insulation between low voltage and high voltage windings is__________________?

(A) 1 + 0.2 kVmm
(B) 2 + 0.5 kVmm
(C) 4 + 0.7 kV mm
(D) 5 + 0.9 kV mm

Submitted By :Ali Uppal

The surge phenomenon is particularly important in case of_______________?

(A) low voltage transformers
(B) medium voltage transformers
(C) high voltage transformers
(D) any of the above

Submitted By :Ali Uppal

The insulation between windings and grounded core and the insulation between the windings of the same phase is called__________________?

(A) minor insulation
(B) major insulation
(C) either of the above
(D) none of the above

Submitted By :Ali Uppal

____________ is the common method of applying brushes to the commntator?

(A) Radial
(B) Trailing
(C) Reaction
(D) All of the above

Submitted By :Ali Uppal

___________ brushes are fragile and cause excessive wear of commutator?

(A) Natural graphite
(B) Hard carbon
(C) Electro graphitic
(D) Metal graphite

Submitted By :Ali Uppal

The laminations of the armature of a D.C. machine are usually ___________ thick?

(A) 0.1 to 0.2 mm
(B) 0.2 to 0.3 mm
(C) 0.3 to 0.4 mm
(D) 0.4 to 0.5 mm

Submitted By :Ali Uppal

The cylindrical windings using circular conductors are used for current rating of____________?

(A) upto 20 A
(B) upto 40 A
(C) upto 60 A
(D) upto 80 A

Submitted By :Ali Uppal

Which of the following in an application of D.C. motors?

(A) Traction
(B) Drives for process industry
(C) Battery driven vehicles
(D) Automatic control
(E) All of the above

Submitted By :Ali Uppal

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