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

$A$ 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

Force acting on an electron moving with velocity $v$ in a magnetic field $B$ is ($e$ is the charge of electron).

An electron is moving at a speed of $3.2 \times 10^7 \ m/s$ in a magnetic field of $12 \times 10^{-4} \ T$ perpendicular to the direction of motion of the electron. The radius of the path of the electron is . . . . . . $cm$. $(e = 1.6 \times 10^{-19} \ C$ and $m_e = 9 \times 10^{-31} \ kg)$

An electron having a charge $e$ moves with a velocity $\vec{v}$ in the positive $x$-direction. $A$ magnetic field $\vec{B}$ acts on it in the positive $y$-direction. The force on the electron acts in (where the outward direction is taken as the positive $z$-axis):

The ratio of periods of $\alpha$-particle and proton moving on circular path in uniform magnetic field is . . . . . . .

Vedclass Test Series

Exam Paper Generator

Online Exam Module