Question

A particle consisting of two electrons is moving in a magnetic field of $(3i+2j)T$ with a velocity $5\times {10}^5\hat{i}m/s$. The magnetic force acting on the particle will be

• A. $3.2\times {10}^{-13}\hat{k}dyne$
• B. $3.2\times {10}^{13}\hat{k}N$
• C. $zero$
• D. $3.2\times {10}^{-13}\hat{k}N$

Answer 1

The correct option is D $3.2\times {10}^{-13}\hat{k}N$

$\overrightarrow{F}=q(\overrightarrow{v}\times \overrightarrow{B})$
$\overline{F}=3\cdot 2\times {10}^{-19}(5\times {10}^5\hat{i}\times (3\hat{i}+2\hat{j}\left)\right)$
$=3.2\times {10}^{-13}\hat{k}N$