An electron is moving along the positive x-ax | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(A) The magnetic force on a moving charge is given by the Lorentz force formula: $\overrightarrow{F} = q(\overrightarrow{v} 	imes \overrightarrow{B})

Vedclass · Accepted Answer

$B$ and $E$ only

Vedclass · Answer

(A) The magnetic force on a moving charge is given by the Lorentz force formula: $\overrightarrow{F} = q(\overrightarrow{v} 	imes \overrightarrow{B})$.For an electron,$q = -e$. The velocity vector is $\overrightarrow{v} = v\hat{i}$ and the magnetic field is $\overrightarrow{B} = -B\hat{k}$.Substituting these values: $\overrightarrow{F} = -e(v\hat{i} 	imes -B\hat{k}) = evB(\hat{i} 	imes \hat{k}) = evB(-\hat{j})$.Thus,the force acts along the negative $y$-axis ($B$ is correct).Since the magnetic force is always perpendicular to the velocity,it acts as a centripetal force,causing the electron to move in a circular path ($E$ is correct).Therefore,the correct options are $B$ and $E$.

Similar Questions

When an electron beam passes through an electric field,it gains kinetic energy. If the same beam passes through a magnetic field,then:

$A$ charged particle is moving in a uniform magnetic field in a circular path of radius $R$. When the energy of the particle becomes three times the original,the new radius will be

$A$ negatively charged particle projected towards east is deflected towards north by a magnetic field. The direction of the magnetic field is

Vedclass Test Series

Exam Paper Generator

Online Exam Module