Embibe Experts Solutions for Chapter: Magnetic Effect of Current, Exercise 5: Exercise (Assertion & Reason)

A charge $q$ moves in a region, where electric field $\overrightarrow{E}$ and magnetic field $\overrightarrow{B}$ both exist. Then the force on it is

A charged particle (charge $q$) is moving in a circle of radius $R$ with uniform speed $v$. The associated magnetic moment $\mu$ is given by

A proton carrying $1\mathrm{MeV}$ kinetic energy is moving in a circular path of radius $\mathrm{R}$ in uniform magnetic field. What should be the energy of an $\alpha$ - particle to describe a circle of same radius in the same field ?

An electron is moving in a circular path under the influence of a transverse magnetic field of $3.57\times {10}^{-2} \mathrm{T}.$ If the value of $e/m$ is $1.76\times {10}^{11}\mathrm{C} {\mathrm{kg}}^{-1}$ the frequency of revolution of the electron is

A proton of mass $1.67\times {10}^{-27} \mathrm{kg}$ and charge $1.6\times {10}^{-19} \mathrm{C}$ is projected with a speed of $2\times {10}^6 \mathrm{m} {\mathrm{s}}^{-1}$ at an angle of $60°$ to the $X$-axis. If a uniform magnetic field of $0.104$ Tesla is applied along $Y-axis,$ the path of proton is-

A long straight wire of radius $a$ carries steady current $\mathfrak{i}.$ The current is uniformly distributed across its cross-section. The ratio of the magnetic field at $\frac{a}{2}$ and $2a$ is 

A current I flows along the length of an infinitely long, straight thin walled pipe. Then 

When a piece of a ferromagnetic substance is put in a uniform magnetic field, the flux density inside it is four times the flux density away from the piece. The magnetic permeability of the material is