Question

why do the planets stay in their orbit around the sun?

Explanation:

Planets stay in orbit due to a balance between the Sun's gravitational pull, which pulls planets inward, and the planets' forward inertial motion, which would carry them straight into space. This stable balance creates a curved orbital path.

Answer:

Planets remain in their orbits around the Sun because of the stable balance between the Sun's gravitational force (which pulls the planet toward the Sun) and the planet's own forward inertial motion (which would carry it in a straight line away from the Sun). This combination results in the curved, continuous orbital path.