Question

The magnetic force acting on a charged particle of charge $-2 \mu C$ in a magnetic field of $2 T$ acting in y direction, when the particle velocity is is $(2 \hat{i} + 3\hat{j}) \times 10^6 \, ms^{-1}$

• A. 4 N in z direction
• B. 8 N in y direction
• C. 8 N in z direction
• D. 8 N in - z direction

Answer 1

Answer: (D)

8 N in - z direction

Answer 2

$\vec{ F } = q (\vec{ v } \times \vec{ B })$
$=-2 \times 10^{-6}\left[(2 \hat{ i }+3 \hat{ j }) \times 10^{6} \times 2 \hat{ j }\right]$
$=-(8 N ) \hat{ k }$