The relationship between the period of revolution (the time it takes for a planet to complete one orbit around the sun) and the distance from the sun is described by Kepler's Third Law of Planetary Motion.

Kepler's Third Law states that the square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit.

Mathematically:

T² ∝ a³

where:

* T is the orbital period (in years)

* a is the semi-major axis of the orbit (in astronomical units, AU)

This means:

* The farther a planet is from the sun, the longer its orbital period. This is because the planet has to travel a larger distance to complete one orbit.

* The relationship is not linear, but rather a power law. This means that a small change in distance from the sun can result in a much larger change in orbital period.

Example:

* Earth is about 1 AU from the sun and has an orbital period of 1 year.

* Mars is about 1.52 AU from the sun and has an orbital period of about 1.88 years.

Important Note:

Kepler's Third Law holds true for all objects orbiting the sun, not just planets. This includes comets, asteroids, and even artificial satellites.