In an industrial electrostatic precipitator, two parallel vertical metal plates separated by a distance h h\,h are used to remove particulate matter from exhaust gases. A potential difference V V\,V is maintained across these plates. A spherical dust grain carrying a net charge q q\,q is situated at a horizontal distance of 0.15h from the negative plate.
What is the magnitude of the electrostatic force acting on this dust grain?
0.15qVh0.15 \frac{qV}{h}0.15hqV
qVh\frac{qV}{h}hqV
qV0.15h\frac{qV}{0.15h}0.15hqV
qV0.85h\frac{qV}{0.85h}0.85hqV
