A particle having the same charge as of electron moves in a circular path of radius $0.5
\,cm$ under the influence of a magnetic field of $0.5\,T.$ If an electric field of $100\,V/m$ makes it to move in a straight path, then the mass of the particle is (given charge of electron $= 1.6 \times 10^{-19}\, C$ )

  • [JEE MAIN 2019]
  • A

    $9.1 \times 10^{-31}\, kg$ 

  • B

    $1.6 \times 10^{-27}\, kg$ 

  • C

    $1.6 \times 10^{-19}\, kg$ 

  • D

    $2.0 \times 10^{-24}\, kg$ 

Similar Questions

Consider the following statements regarding a charged particle in a magnetic field . Which of the statements are true :

A very high magnetic field is applied to a stationary charge. Then the charge experiences

 A charged particle (electron or proton) is introduced at the origin $(x=0, y=0, z=0)$ with a given initial velocity $\overrightarrow{\mathrm{v}}$. A uniform electric field $\overrightarrow{\mathrm{E}}$ and magnetic field $\vec{B}$ are given in columns $1,2$ and $3$ , respectively. The quantities $E_0, B_0$ are positive in magnitude.

column $I$

column $II$ column $III$
$(I)$ Electron with $\overrightarrow{\mathrm{v}}=2 \frac{\mathrm{E}_0}{\mathrm{~B}_0} \hat{\mathrm{x}}$ $(i)$ $\overrightarrow{\mathrm{E}}=\mathrm{E}_0^2 \hat{\mathrm{Z}}$ $(P)$ $\overrightarrow{\mathrm{B}}=-\mathrm{B}_0 \hat{\mathrm{x}}$
$(II)$ Electron with $\overrightarrow{\mathrm{v}}=\frac{\mathrm{E}_0}{\mathrm{~B}_0} \hat{\mathrm{y}}$ $(ii)$ $\overrightarrow{\mathrm{E}}=-\mathrm{E}_0 \hat{\mathrm{y}}$ $(Q)$ $\overrightarrow{\mathrm{B}}=\mathrm{B}_0 \hat{\mathrm{x}}$
$(III)$ Proton with $\overrightarrow{\mathrm{v}}=0$ $(iii)$ $\overrightarrow{\mathrm{E}}=-\mathrm{E}_0 \hat{\mathrm{x}}$ $(R)$ $\overrightarrow{\mathrm{B}}=\mathrm{B}_0 \hat{\mathrm{y}}$
$(IV)$ Proton with $\overrightarrow{\mathrm{v}}=2 \frac{\mathrm{E}_0}{\mathrm{~B}_0} \hat{\mathrm{x}}$ $(iv)$ $\overrightarrow{\mathrm{E}}=\mathrm{E}_0 \hat{\mathrm{x}}$ $(S)$ $\overrightarrow{\mathrm{B}}=\mathrm{B}_0 \hat{\mathrm{z}}$

($1$) In which case will the particle move in a straight line with constant velocity?

$[A] (II) (iii) (S)$    $[B] (IV) (i) (S)$   $[C] (III) (ii) (R)$   $[D] (III) (iii) (P)$

($2$) In which case will the particle describe a helical path with axis along the positive $z$ direction?

$[A] (II) (ii) (R)$   $[B] (IV) (ii) (R)$  $[C] (IV) (i) (S)$   $[D] (III) (iii)(P)$

($3$)  In which case would be particle move in a straight line along the negative direction of y-axis (i.e., more along $-\hat{y}$ )?

$[A] (IV) (ii) (S)$   $[B] (III) (ii) (P)$   $[C]$ (II) (iii) $(Q)$   $[D] (III) (ii) (R)$

  • [IIT 2017]

A uniform magnetic field $B$ is acting from south to north and is of magnitude $1.5$ $Wb/{m^2}$. If a proton having mass $ = 1.7 \times {10^{ - 27}}\,kg$ and charge $ = 1.6 \times {10^{ - 19}}\,C$ moves in this field vertically downwards with energy $5\, MeV$, then the force acting on it will be

An electron is travelling along the $x$-direction. It encounters a magnetic field in the $y$-direction. Its subsequent motion will be

  • [AIIMS 2003]