Question

A particle of charge $16\times {10}^{-18}C$ moving with velocity $10m/s$ along the X-axis enters a region where a magnetic field of induction $B$ is along the Y-axis, and an electric field of magnitude $10V{m}^{-1}$ is along the negative Z-axis. If the charged particle continues moving along the X-axis, the magnitude of $B$ is :

• A. $1Wb/m^2$
• B. ${10}^{5}Wb/m^2$
• C. ${10}^{6}Wb/m^2$
• D. ${10}^{-3}Wb/m^2$

Answer 1

Answer: (A)

$1Wb/m^2$

Since particle continues moving along X-axis, so there should be no force on the particle.
$F_{net}=0$
$F_{electic}-F_{magnetic}=0$
$qE=qvB$
$E=vB$
$10=10\times B$
$B=1Wb-m^2$