A certain amount of current flows through a ring shaped coil with fixed number of turns. How does the magnetic induction B varies inside the coil if an iron core is threaded into coil without dimensional change of coil?
A. Decreases
B. Increases
C. Remains same
D. First increases and then decreases depending on the depth of iron in¬sertion
Answer: Option B
This Question Belongs to Electrical Engineering >> Magnetism And Electromagnetism
Which of the following is a vector quantity?
A. Relative permeability
B. Magnetic field intensity
C. Flux density
D. Magnetic potential
What is the magneto-motive force (mmf) of a wire with 8 turns carrying three amperes of current?
A. 2,400 At
B. 240 At
C. 24 At
D. 2.4 At
Magnetism of a magnet can be destroyed by
A. heating
B. hammering
C. by inductive action of another magnet
D. by all above methods
Strength of an electromagnet can be increased by
A. increasing the cross-sectional area
B. increasing the number of turns
C. increasing current supply
D. all above methods
Join The Discussion