Answer:
The excess charge is
Explanation:
From the question we are told that
The diameter is 
The potential of the surface is 
The radius of the sphere is

substituting values


The potential on the surface is mathematically represented as

Where k is coulomb's constant with value 
given from the question that there is no other charge the Q is the excess charge
Thus

substituting values


Explanation:
(A) Electric field for the parallel plate capacitor is given by :

It is clear that the electric field does not depend on the separation of the plates.
(B) The relation between the electric field and the electric potential is given by :

d is the separation between plates. So, if the separation of the plates is increased, the potential difference increases.
(C) The capacitance of the parallel plate capacitor is given by :

So, the capacitance decreases when the separation of the plates is increased.
(D) The energy stored in the capacitor is given by :


So, the energy stored in the capacitor is increased when the separation of the plates is increased.
You should solve this like you would any algebraic expression. Divide both sides by acceleration (a) and you will isolate the mass (m) to one side. Now divide the force (f) by acceleration (a).
F/a=m
C. coil suspended by bearings.
<span>but im not 100% sure</span>
Then, it would continue the motion in direction of resultant force...