Electrical Machine - I (3140913) MCQs

MCQs of Magnetic fields and magnetic circuits

Showing 31 to 30 out of 40 Questions
1 2 3 4
31.
Lines of magnetic flux which are parallel and in the same direction __________ each other.
(a) Attract
(b) Repel
(c) Intersect
(d) Cancel
Answer:

Option (b)

32.
The force existing between two infinite parallel conductors is inversely proportional to ________
(a) The radius of the conductors
(b) Current in one of the conductors
(c) The product of the current in the two conductors
(d) The distance between the two conductors
Answer:

Option (d)

33.
The magnetic field at a point d distance away from long wire due to the electric current I in it is ____________
(a) µ0I/2r
(b) µ0I/r
(c) µ0I/2πr
(d) µ0I/πr
Answer:

Option (c)

34.
If the radius of the current carrying conductor increases, what is the effect on the force
(a) increases
(b) decreases
(c) remain the same
(d) become zero
Answer:

Option (c)

35.
The force per unit length existing between two infinite parallel conductors is given by ___________
(a) μ0 I1 I22 π d
(b) μ0 I1 I22 d
(c) μ0 I1 I2 d
(d) μ0 I1d
Answer:

Option (a)

36.
If the length of current carrying conductor increases, what is the effect on the force?
(a) increases
(b) decreases
(c) remain the same
(d) become zero
Answer:

Option (a)

37.
The magnetic field strength of a solenoid can be increased by inserting which of the following materials as the core?
(a) Copper
(b) Silver
(c) Iron
(d) Aluminum
Answer:

Option (c)

38.
What is the formula for the magnetic field due to a solenoid?
(a) μnI
(b) μn2
(c) μI2
(d) μn2I2
Answer:

Option (a)

39.
What happens to the magnetic field in the solenoid when the length of the solenoid increases?
(a) Increases
(b) Decreases
(c) Remains constant
(d) Becomes zero
Answer:

Option (b)

40.
What is the expression for force in a current carrying conductor?
(a) F=K/r2
(b) F=Kq/r2
(c) F=Kq1q2/r2
(d) F=Kq1q2/r
Answer:

Option (c)

Showing 31 to 30 out of 40 Questions
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