Answer:

Explanation:
As we know that the charge per unit length of the long cylinder is given as

here we know that the electric field between two cylinders is given by

now we know that electric potential and electric field is related to each other as





Answer:
The spring constant is 3750 N/m
Explanation:
Use the following two relationships:
(Work) = (Force) x (Displacement)
(Force) = (Spring constant) x (Displacement)
=>
(Spring constant) = (Force) / (Displacement) = (Work) / (Displacement)^2
(Spring constant) = 6.0 kg.(m^2/s^2) / 0.0016 m^2 = 3750 N/m
The spring constant is 3750 N/m