Q. In Bainbridge mass spectrograph a potential difference of $1000\ V$ is applied between two plates distant $1\ cm$ apart and magnetic field $B = 1T.$ The velocity of undeflected positive ions in $m/s$ from the velocity selector is
A) $10^{7}\ m/s$
B) $10^{4}\ m/s$
C) $10^{5}\ m/s$
D) $10^{2}\ m/s$
Explanation
(c) $v = \frac{E}{B};where\ E = \frac{V}{d} = \frac{1000}{1 \times 10^{- 2}} = 10^{5}V/m$
$\Rightarrow v = \frac{10^{5}}{1} = 10^{5}m/s$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.