How does inertia and gravity affect the orbital motion planets?

Inertia and gravity are fundamental forces that govern the orbital motion of planets. Inertia, as described by Newton's first law of motion, causes planets to continue moving in a straight line unless acted upon by an external force. Meanwhile, gravity, the attractive force between masses, pulls planets toward the sun, creating a curved path. The balance between these two forces results in stable orbits, where planets continually fall toward the sun but also move forward, preventing them from crashing into it.