Electromechanical Energy Conversion Principle MCQs

Q 1. The developed electromagnetic force and/or torque in the electromechanical energy conversion system act in a direction that tends _______.

A. to increase the stored energy at constant flux
B. to decrease the stored energy at constant flux
C. to decrease the stored energy at constant mmf
D. to increase the stored energy at constant mmf

Answer
Answer. b

Q 2. In electromechanical energy conversion devices (e.g. generators and motors), a small air gap is left between the stator and rotor in order to ______.

A. reduce the reluctance of the magnetic path
B. increase flux density in the air gap
C. permit mechanical clearance
D. avoid saturation of the field

Answer
Answer. c

Q 3. A circular metallic disc is placed in a vertical magnetic field of constant induction in the downward direction. If the disc is rotated in a horizontal plane, the mmf induced will be ______.

A. zero
B. constant and independent of disc size
C. increasing radially in the outward direction
D. decreasing radially in the outward direction

Answer
Answer. a