An electric field of 1500, V/m and a magnetic field of 0.40, weber/metre^2 act on a movin

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4.Moving Charges and Magnetism

medium

An electric field of $1500\, V/m$ and a magnetic field of $0.40\, weber/metre^2$ act on a moving electron. The minimum uniform speed along a straight line the electron could have is

A

$1.6 \times 10^{15} \,m/s$

B

$6 \times 10^{-16} \,m/s$

C

$3.75 \times 10^{3} \,m/s$

D

$3.75 \times 10^{2} \,m/s$

Solution

When the electron moves in both electric and magnetic fields then :

$\mathrm{q} \mathrm{E}=\mathrm{qvB}$

$\therefore $ $v=$ $\frac{E}{B}-\frac{1500}{0.40}=370\, \mathrm{m} / \mathrm{s}$

$=3.75 \times 10^{3}\, \mathrm{m} / \mathrm{s}$

Standard 12

Physics

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