What is the relationship between kinetic and potential energy in a roller coaster.

 Kinetic energy is energy that an object has as a result of its motion. Potential energy is stored energy that has not yet been released.

Explanation:  All moving objects possess kinetic energy, which is determined by the mass and speed of the object. Potential energy is the energy an object has as a result of its position.

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.