What is a purpose of a capacitor?

The purpose of a capacitor is to store energy in the electric field between a pair of closely spaced conductors that are called plates, and these capacitors are used in electrical circuits as energy-storage devices.

A person's risk of sunburn on a certain body part is greater the more directly the Sun's rays hit that body part. If a person is walking outside with the Sun directly overhead, what body part has the greatest risk for sunburn? (Assume that none of the body parts mentioned below are covered by a hat or hair or anything.)