Electromagnetics Field (3140912) MCQs
MCQs of Magnetic forces, materials and inductance
| 141. |
An average voltage of 10 V is induced in a 250 turns solenoid as a result of a change in flux which occurs in 0.5 second. The total flux change is
|
||||||||
|
Answer:
Option (d) |
| 142. |
A 500 turns solenoid develops an average induced voltage of 60 V. Over what time interval must a flux change of 0.06 Wb occur to produce such a voltage ?
|
||||||||
|
Answer:
Option (c) |
| 143. |
Which of the following inductor will have the least eddy current losses?
|
||||||||
|
Answer:
Option (a) |
| 144. |
Two 300 μH coils in series without mutual coupling have a total inductance of
|
||||||||
|
Answer:
Option (b) |
| 145. |
When a current changing from 8 A to 12 A in one second in a coil, induced is 20 V. The value of inductance is
|
||||||||
|
Answer:
Option (c) |
| 146. |
A crack in the magnetic path of an inductor will result in
|
||||||||
|
Answer:
Option (d) |
| 147. |
A coil is wound on iron core which carries current I. The self-induced voltage in the coil is not affected by
|
||||||||
|
Answer:
Option (b) |
| 148. |
A moving magnetic field will produce the same effect as a conductor that is moving.
|
||||||||
|
Answer:
Option (a) |
| 149. |
Increasing the field or increasing the current will decrease the force on the conductor.
|
||||||||
|
Answer:
Option (b) |
| 150. |
What will be the magnitude of the force exerted on the charge by the fields B = −3āx+4āy+6āz mT and E = −3āx+4āy+6āz kV/m when a charge of 18 nC is moving with a velocity of 5×106 m/s in the direction of 0.6āx+0.75āy+0.3āz.
|
||||||||
|
Answer:
Option (c) |
Developed by
