What is the electric force require to balance the weight of the oil droplet?

I am thoroughly confused on this question.





Millikan鈥檚 experiment measures the charge of an electron by suspending charged oil droplets in an electric field. If an oil droplet with a mass of 3.35 脳 10鈥?5 kg has the same charge as an electron. What electric force is required to balance the weight of the oil droplet?What is the electric force require to balance the weight of the oil droplet?
Electrical force = weight


= m*g


= 3.35*10^-15 * 9.8


= 3.283 * 10^-14





is you want to know the electric field intensity then replace electric force by qE. Divide both sides by q=-1.6*10^-19 to get E.What is the electric force require to balance the weight of the oil droplet?
Electric Field(E) = (4/3)(pi)((r)^3)[Q]/r^2. Here Q is the charge creating the electric field.





E.q=3.35x10^(-15) x 9.81 Newton.





where q is the charge of an electron.





Given either of E or q, one may find the other.