Electrical Engineering Daily Quiz 10th April 2022 NBCC JE 2017 Solution
Question : 1
Direction of rotation of DC shunt motor can be reversed by interchanging
A. The armature terminal only
B. Either field or armature terminal
C. The supply terminal
D. The field terminals only
Answer-B
Question : 2
Use of starters in DC motors is necessary
A.To overcome back emf
B. They are not self-starting
C. To limit high initial current by inserting high resistance
D. None of these
Answer-C
Question : 3
Scott connection is used to transform
A. Single phase supply in two phase supply
B. Two phase unbalanced supply into three phase balanced supply
C. Three phase supply into two phase supply
D. Two phase supply into single phase supply
Answer-C
Question : 4
Three phase transformers connection preferable for step up operation is
A. Y-Y
B. Δ-Δ
C. Y-Δ
D. Δ-Y
Answer-D
Question : 5
For short circuit test and open circuit test of transformers the instruments are connects on
A. LV side and HV side respectively
B. HV side and LV side respectively
C. HV side only
D. LV side only
Answer-D
Question : 6
In Merz Price differential protection of a Delta Star transformer, the CTs are connected in primary and secondary winding in a
A. Delta Star connection
B. Star Star connection
C. Star Delta connection
D. Any of these
Answer-C
Question : 7
A DC shunt motor is
A. Variable speed motor
B. Adjustable speed motor
C. Constant speed motor
D. Constant speed adjustable speed motor
Answer-C
Question : 8
Speed of DC shunt motor is
A. Proportional to the square of armature current
B. Inversely proportional to armature current
C. Independent of armature current
D. Directly proportional to armature current
Answer-C
Question : 9
In synchronous motor
A. The generated emf must always be less than terminal voltage
B. The generated emf must always more than terminal voltage
C. The generated voltage can be less than or greater than terminal voltage
D. None of these
Answer-C
Question : 10
While starting synchronous motor its field winding should be
A. Kept open
B. Connected to a DC source
C. Connected to a AC source
D. Kept short circuited
