# Coulombs homework problem

1. Dec 6, 2003

### marshall4

What charge is required to suspend a 1.7*10^-13kg oil drop in an electric field of 2.5*10^5 N/C?

2. Dec 8, 2003

### himanshu121

Draw the Free Body Diagram
Apply $$\Sigma F$$ = $$\vec F_m_a_g + \vec F_w_t$$ = 0
As in case of equilibrium

Also apply the charge quantization