Moving Charges & Magnetism - Physics PYQ (AP EAPCET)

The magnetic field, of a given length of wire for single turn coil, at its centre is B, then its value for two turns coil for the same wire is

In a co-axial, straight cable, the central conductor and the outer conductor carry equal currents in opposite directions. The magnetic field is zero

In which of the following case no force exerted by a magnetic field on a charge?

A long thin hollow metallic cylinder of radius R has a current i ampere. The magnetic induction B away from the axis at a distance r from the axis varies as shown in

Torque required to hold a small circular coil of 10 turns, area of \(2 \times 10^{-4} \mathrm{~m}^2\) area of carrying 0.5 A current in the middle of a long solenoid of \(10^3\) turns per metre carrying \(3 \mathrm{~A}\) current, with its axis perpendicular to the axis of the solenoid is

Two concentric coils each of radius equal to \(4 \pi ~\mathrm{cm}\) are placed at right angles to each other. If \(10 \mathrm{~A}\) and \(24 \mathrm{~A}\) are the currents flowing through the coils respectively, then the magnetic induction at the centre of the coils will be

A wire of length \(L\) metre carrying a current \(I\) ampere is bent in the form of a circle. Magnitude of its magnetic moment is

What is the net force on the square coil?

A toroid has a non ferromagnetic core of inner radius 24 cm and outer radius 25 cm , around which 4900 turns of a wire are wound. If the current in the wire is 12 A , the magnetic field inside the core of the toroid is

Two electrons, \(e_1\) and \(e_2\) of mass \(m\) and charge \(q\) are injected into the perpendicular direction of the magnetic field \(B\) such that the kinetic energy of \(e_1\) is double than that of \(e_2\). The relation of their frequencies of rotation, \(f_1\) and \(f_2\) is

Two infinitely long wires each carrying the same current and pointing in \(+y\) direction are placed in the \(x y\)-plane, at \(x=-2 \mathrm{~cm}\) and \(x=1 \mathrm{~cm}\). An electron is fired with speed \(u\) from the origin making an angle of \(+45^{\circ}\) from the \(X\)-axis. The force on the electron at the instant it is fired is

[\(B_0\) is the magnitude of the field at origin due to the wire at \(x=1 \mathrm{~cm}\) alone].

An electron having kinetic energy of 100 eV circulates in a path of radius 10 cm in a magnetic field. The magnitude of magnetic field \(|\mathbf{B}|\) is approximately [Mass of electron \(=0.5 \mathrm{~MeV} \mathrm{c}^{-2}\), where c is the velocity of light].

A particle of mass \(2.2 \times 10^{-30} \mathrm{~kg}\) and charge \(1.6 \times 10^{-19} \mathrm{C}\) is moving at a speed of \(10 \mathrm{~km} \mathrm{~s}^{-1}\) in a circular path of radius 2.8 cm inside a solenoid. The solenoid has \(25 \frac{\text { turns }}{\mathrm{cm}}\) and its magnetic field is perpendicular to the plane of the particle's path. The current in the solenoid is

(Take, \(\mu_0=4 \pi \times 10^{-7} \mathrm{~Hm}^{-1}\))