Question

An alpha particle in an electric field of intensity $E$ experiences the same force as when it moves perpendicular to a magnetic field of induction $B$. The magnitude of its velocity in the magnetic field is given by

• A. $\frac{B}{E}$
• B. $\frac{E}{B}$
• C. $\frac{B^2}{E}$
• D. $\frac{E^2}{B}$

Answer 1

The correct option is B $\frac{E}{B}$

$\because$ alpha particle experience same force in electric field as in magnetic field
So, $f_E=f_B$
$qE=qVB$
$V=\frac{E}{B}$