Answer to Question #258258 in Electricity and Magnetism for zuzu

Question

a) Find the electric potential of a point located at a distance of 0.8 m from a charge of q = -8mC.

b) Find the magnitude of the force exerted by the field E over a particle with a charge of q=+9x10^-9C

Answer 1

a)

$\varphi=-\frac{kq}r=90~MV,$

b)

$F=\frac{k|q_1||q_2|}{r^2}=1.01~N.$