JEE Physics - MCQ Practice Questions

Which of the following is NOT a property of magnetic field lines?

A straight wire carrying current I is placed in a uniform magnetic field B at an angle θ to the magnetic field. If the length of the wire is L, the magnetic force on the wire is:

Two parallel wires carry currents I₁ and I₂ in the same direction, separated by distance d. The force per unit length between them is:

A charged particle enters a uniform magnetic field with velocity perpendicular to the field. The particle will move in:

A solenoid has n turns per unit length and carries current I. The magnetic field inside the solenoid is:

The magnetic moment of a current loop is defined as:

An electron moves in a plane perpendicular to a uniform magnetic field. If the radius of its circular path is r, the momentum of the electron is:

The magnetic field between the poles of a permanent magnet is approximately:

A rectangular conducting loop ABCD with sides a and b is rotated with angular velocity ω in a uniform magnetic field B perpendicular to the plane of rotation. The induced EMF is:

Two magnets are placed with their north poles facing each other. The force between them varies with distance r as:

A conducting rod of length L moves with velocity v perpendicular to its length in a magnetic field B. The motional EMF induced is maximum when:

The magnetic susceptibility of a paramagnetic material is:

A charged particle with charge q and mass m is moving with speed v in a circular path of radius r in a magnetic field. The magnetic field strength is:

The permeability of free space μ₀ has the value:

A long straight wire carrying current I produces a magnetic field at distance r. If the current is doubled and distance is halved, the magnetic field becomes:

The SI unit of magnetic flux density (magnetic field) is:

A proton and an alpha particle (He²⁺ nucleus) are accelerated through the same potential difference. They are then made to move perpendicular to a uniform magnetic field. The ratio of their radii of curvature is:

A rectangular loop of dimensions a × b is placed in a non-uniform magnetic field where B varies as B = B₀(1 + kx), where x is the distance from a reference line. The net force on the loop is:

A charged particle enters a region with perpendicular electric and magnetic fields with velocity v. For the particle to pass undeflected, the condition is:

A solenoid with N turns, length L, and cross-sectional area A is wound with wire of resistance R. When connected to a voltage source V, the magnetic energy stored is: