Question

Calculate the electric field strength required to just support a water drop of mass 10^-7 kg and having charge 1.6x10^-9 C?

Answer 1

Gravitational Force on water=10^-7*9.8kgm/s^2. Now force due to electric field=qE where q is charge and E is feild. Now we have to balance water so mg=qE we have calculated mg above so now E can be calculated