An ion has a charge of +3.2 x 1014 C. Another charge is brought near it and experiences a repulsive electrostatic force. This other charge must be

Positive.

Explanation:

Given that the ion has a charge of +3.2 x 10^14 C.

When another charge is brought near it, it experiences a repulsive electrostatic force. The other charge brought near the ion must be positive.

This is because the electric field which is a region of space created by the positive ion with a charge of +3.2 x 1014 C have electric lines of force moving outward. Therefore, when another charge is brought near the positive ion, it will either attract or repel depending on the charge of the ion brought into the electric field created by the positive ion.

If the charge on the second ion is also positive, the electric lines of force will be in the same direction as that on the first ion and will their repel. However, if the second ion is negative, the electric field lines are in the opposite direction to that of the first positive ion, thereby creating an attractive electrostatic force in the electric field.

In summary, like charges repel, unlike charges attract.

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.