A satellite orbits a planet in a circular path at a radius R. If the orbital speed of the satellite is v, and the mass of the planet is M, what is the correct expression for the orbital speed? (G is the gravitational constant)
✓ Correct Answer: Option A
For a circular orbit, gravitational force (GmM/R²) provides the centripetal force (mv²/R). Equating them gives mv²/R = GmM/R², which simplifies to v² = GM/R, so v = √(GM/R).