21) The armature core of DC generators are commonly mad of

Iron

Silicon steel

High carbon steel

Stainless steel

Answer is:

Silicon steel

ISRO Technician-B Electrician Question Paper - 2017 (Set - 1) with Answer Key

For more MCQ's Click Here

22) If field circuit of a DC shunt motor gets opened at light load, then

The motor pickup very high speed

The motor will slow down

The motor will stop

The motor will run normally

Answer is:

The motor pickup very high speed

23) Motor used in electric traction is

DC compound

DC shunt

DC series

DC long shunt compound

Answer is:

DC series

24) Which method is NOT correct to change the direction of rotation of a DC series motor?

By changing the polarity of supply terminal

By changing the terminal of series field

By interchanging brush contact position

By changing the terminals of the armature

Answer is:

By changing the polarity of supply terminal

25) The rotational speed of a DC shunt motor can be increased above its full speed by

Increasing field current

Decreasing field current

Increasing armature current

Decreasing armature current

Answer is:

Decreasing field current

ISRO Technician-B Electrician Question Paper - 2017 (Set - 1) with Answer Key

For more MCQ's Click Here

21) The armature core of DC generators are commonly mad of

Silicon steel

ISRO Technician-B Electrician Question Paper - 2017 (Set - 1) with Answer Key

Related ISRO Technician-B Electrician Question Paper - 2017 (Set - 1) with Answer Key

22) If field circuit of a DC shunt motor gets opened at light load, then

The motor pickup very high speed

23) Motor used in electric traction is

DC series

24) Which method is NOT correct to change the direction of rotation of a DC series motor?

By changing the polarity of supply terminal

25) The rotational speed of a DC shunt motor can be increased above its full speed by

Decreasing field current

ISRO Technician-B Electrician Question Paper - 2017 (Set - 1) with Answer Key