MCQs of Moving Charges & Magnetism

Moving Charges & Magnetism MCQs

MCQs of Moving Charges & Magnetism

Showing 31 to 40 out of 123 Questions

31.

Two very long conducting parallel wires are separated by a distance d from each other and equal currents are passed through them in mutually opposite directions. A particle of charge q passes through a point, at a distance

\frac{d}{2}

from both wires, with velocity v perpendicularly to the plane formed by the wires. The resultant magnetic force acting on this particle is _____ .

(a)	$\frac{μ_{0} I q v}{2 π d}$
(b)	$\frac{μ_{0} I q v}{π d}$
(c)	$\frac{2 μ_{0} I q v}{π d}$
(d)	zero

32.

A very long solenoid of length L has n layers. There are N turns in each layer. Diameter of the solenoid is D and it carries current I. The magnetic field at the centre of the solenoid is _____ .

(a)	directly proportional to D.
(b)	inversely proportional to D.
(c)	independent of D.
(d)	directly proportional to L.

33.

The angular speed of the charged particle is independent of _____ .

(a)	its mass.
(b)	its linear speed.
(c)	charge of particle.
(d)	magnetic field.

34.

A charged particle gains energy due to _____ .

(a)	electric field.
(b)	magnetic field.
(c)	both these fields.
(d)	none of these fields.

35.

A charged particle is moving with velocity

\vec{v}

in a uniform magnetic field

\vec{B}

. The magnetic force acting on it will be maximum when _____ .

(a)	$\vec{v}$ and $\vec{B}$ are in same direction.
(b)	$\vec{v}$ and $\vec{B}$ are in opposite direction.
(c)	$\vec{v}$ and $\vec{B}$ are mutually perpendicular.
(d)	$\vec{v}$ and $\vec{B}$ make an angle of 45º with each other.

36.

Equal currents are passing through two very long and straight parallel wires in mutually opposite directions. They will _____ .

(a)	attract each other.
(b)	repel each other.
(c)	lean towards each other.
(d)	neither attract nor repel each other.

37.

A charged particle is moving in a uniform magnetic field. Then _____ .

(a)	its momentum changes but kinetic energy does not change.
(b)	its momentum and kinetic energy both changes.
(c)	neither the momentum nor kinetic energy changes.
(d)	kinetic energy changes but the momentum does not change.

38.

If the speed of a charged particle moving through a magnetic field is increased, then the radius of curvature of its trajectory will _____ .

(a)	decrease
(b)	increase
(c)	not change
(d)	become half

39.

Magnetic field produced at the centre of circular coil having radius 0.1 m and 2 turns is _____ if

\frac{1}{4 π}

A current passes through it.

(a)	10 x 10^-6 T
(b)	0.1 x 10^-6 T
(c)	1 x 10^-6 T
(d)	0.01 x 10^-6 T

40.

Maximum magnetic field on electron moving with velocity 4 x 10⁴ m/s is _____ when it moves in magnetic field having intensity 5 x 10^-5 T.

(a)	1.6 x 10^-19 N
(b)	3.2 x 10^-19 N
(c)	1.6 x 10^-17 N
(d)	3.2 x 10^-17 N

Showing 31 to 40 out of 123 Questions