An electron enters the space between the plates of a charged capacitor as shown. The charge density on the plate is $\sigma $. Electric intensity in the space between the plates is $E$. A uniform magnetic field $B$ also exists in that space perpendicular to the direction of $E$. The electron moves perpendicular to both $\vec E$ and $\vec B$ without any change in direction. The time taken by the electron to travel a distance $\ell $ is the space is
An electron enters the space between the plates of a charged capacitor as shown. The charge density on the plate is $\sigma $. Electric intensity in the space between the plates is $E$. A uniform magnetic field $B$ also exists in that space perpendicular to the direction of $E$. The electron moves perpendicular to both $\vec E$ and $\vec B$ without any change in direction. The time taken by the electron to travel a distance $\ell $ is the space is
- A
$\frac{{\sigma \ell }}{{{\varepsilon _0}B}}$
- B
$\frac{{\sigma B }}{{{\varepsilon _0 \ell }B}}$
- C
$\frac{{{\varepsilon _0}\ell B}}{\sigma }$
- D
$\frac{{{\varepsilon _0}\ell }}{{\sigma B}}$
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