A small charged piece of Styrofoam is suspended between two large plates that produce a uniform electric field between them. The mass of the Styrofoam is ?=4.3×10−6??m=4.3×10−6kg, the plates are held at a potential difference of ?=120?V=120V and the plates are a distance of 10??10cm apart. How many excess electrons are on the Styrofoam?

A small charged piece of Styrofoam is suspended between two large plates that produce a uniform electric field between them. The mass of the Styrofoam is ?=4.3×10−6??m=4.3×10−6kg, the plates are held at a potential difference of ?=120?V=120V and the plates are a distance of 10??10cm apart. How many excess electrons are on the Styrofoam?