Question

a charge of 5c and 3kg mass is in vertical equilibrium due to electric field E find the electric field E.

Answer 1

According to the second Newton's law, gravitational force and Lorenz force must compensate each other.

$mg = qE$

$\displaystyle E=\frac{mg}{q}= \frac{3 \cdot 9.81}{5}=5.886 \approx 5.9 \, \frac{V}{m}$

Answer: $5.9 \, \frac{V}{m}$