List of top Physics Questions on Moving charges and magnetism asked in KCET

A positively charged particle of mass m is passed through a velocity selector. It moves horizontally rightward without deviation along the line y = \(\frac{2mv}{qB}\) with a speed v. The electric field is vertically downwards and magnetic field is into the plane of the paper. Now, the electric field is switched off at t = 0. The angular momentum of the charged particle about origin O at t = \(\frac{\pi m}{qB}\) is

A metallic rod of mass per unit length $0.5 \, kg \, m^{-1}$ is lying horizontally on a smooth inclined plane which makes an angle of $30^{\circ}$ with the horizontal. The rod is not allowed to slide down by flowing a current through it when a magnetic field of induction $0.25 \,T$ is acting on it in the vertical direction. The current flowing in the rod to keep it stationary is

A tightly wound long solenoid has ‘n’ turns per unit length, a radius ‘r’ and carries a current I. A particle having charge ‘q’ and mass ‘m’ is projected from a point on the axis in a direction perpendicular to the axis. The maximum speed of the particle for which the particle does not strike the solenoid is

A toroid with thick windings of $N$ turns has inner and outer radii $R_{1}$ and $R_{2}$ respectively. If it carries certain steady current I, the variation of the magnetic field due to the toroid with radial distance is correctly graphed in

The ratio of magnetic field and magnetic moment at the centre of a current carrying circular loop is $x$. When both the current and radius is doubled the ratio will be

In a cyclotron, a charged particle :

In a cyclotron, a charged particle

In a permanent magnet at room temperature

A toroid has 500 turns per metre length. If it carries a current of 2A, the magnetic energy density inside the toroid is

A charge q is accelerated through a potential difference V. It is then passed normally through a uniform magnetic field, where it moves in a circle of radius r. The potential difference required to move it in a circle of radius 2r is

A cyclotron?s oscillator frequency is 10 MHz and the operating magnetic field is 0.66 T. If the radius of its dees is 60 cm, then the kinetic energy of the proton beam produced by the accelerator is

A galvanometer of resistance $50\, O$ is connected to a battery of $3V$ along with a resistance of $2950\, O$ in series shows full-scale deflection of $30$ divisions. The additional series resistance required to reduce the deflection to $20$ divisions is

A proton, a deuteron and an $\alpha$ - particle are projected perpendicular to the direction of a uniform magnetic field with same kinetic energy. The ratio of the radii of the circular paths described by them is

A conducting wire carrying current is arranged as shown. The magnetic field at $'O'$

A galvanometer of resistance $50\, \Omega$ gives a full scale deflection for a current $5\times10^{-4}$. The resistance that The resistance that should be connected in series with the galvanometer to read $3 \,V$ is

A cyclotron is used to accelerate

What is the value of shunt resistance required to convert a galvanometer of resistance $100$ $\Omega$ into an ammeter of range $1\,A$ ? Given : Full scale deflection of the galvanometer is $5 \,mA$

A circular coil of radius $10 \,cm$ and $100$ turns carries a current $1\,A$. What is the magnetic moment of the coil ?

Pick out the wrong statement.

In the loop shown, the magnetic induction at the point $O$ is

A particle of charge $e$ and mass $m$ moves with a velocity $v$ in a magnetic field $B$ applied perpendicular to the motion of the particle. The radius $r$ of its path in the field is

A neutron, a proton, an electron and an $\alpha$-particle enter a region of uniform magnetic field with the same velocities. The magnetic field is perpendicular and directed into the plane of the paper. The tracks of the particles are labelled in the figure. The electron follows the track

The deflection in a moving coil galvanometer is reduced to half when it is shunted with a $40\, \Omega$ coil. The resistance of the galvanometer is

Two thick wires and two thin wires, all of same material and same length, form a square in three different ways $P, Q$ and $R$ as shown in the figure. With correct connections shown, the magnetic field due to the current flow, at the centre of the loop will be zero in case of...........

Magnetic field at the centre of a circular coil of radius $R$ due to current $I$ flowing through it is $B$. The magnetic field at a point along the axis at distance $R$ from the centre is........