Umakant Kondapure, Collin Fernandes, Nipun Bhatia, Vikram Bathula and, Ketki Deshpande Solutions for Chapter: Magnetic Effect of Electric Current, Exercise 2: Critical Thinking

A uniform conducting wire $ABC$ has a mass of $10 \mathrm{g}$. A current of $2 \mathrm{A}$ flows through it. The wire is kept in a uniform magnetic field $B=2 \mathrm{T}$. The acceleration of the wire will be,

The work done by a magnetic field on moving charge is,

For a given perimeter in plane following are some shapes mentioned. Choose the shape for the loop such that which when placed inside magnetic field will have maximum torque acting on it.

Three long straight wires are connected parallel to each other across a battery of negligible internal resistance. The ratio of their resistance are $3: 4: 5.$ What is the ratio of distances of middle wire from the others if the net force experienced by it is zero?

A horizontal rod of mass $10 \mathrm{g}$ and length $10 \mathrm{cm}$ is placed on a smooth plane inclined at an angle of $60°$ with the horizontal, with the length of the rod parallel to the edge of the inclined plane. A uniform magnetic field of induction $B$ is applied vertically downwards. If the current through the rod is $1.73 \mathrm{A}$, then the value of $B$ for which the rod remains stationary on the inclined plane is,

A particle of charge $q$ and mass $m$ is moving along the $X$-axis with a velocity $v$ and enters a region of electric field $E$ and magnetic field $B$ as shown in figure below. For which figure the net force on the charge may be zero?

In Bohr's model of hydrogen atom, the electron circulates around nucleus in a path of radius $0.5 Å$ at a frequency of $6.8\times {10}^{15} \mathrm{rev} {\mathrm{s}}^{-1}$. The magnetic field at the centre will be,

A horizontal wire carries $200 \mathrm{A}$ current below which another wire of linear density $20\times {10}^{-3} \mathrm{kg} {\mathrm{m}}^{-1}$ carrying a current is kept at $2 \mathrm{cm}$ distance. If the wire kept below hangs in air, what is the current in this wire?