Learning Objective: Understand how kinetic, potential, and total energy change with orbital radius, and discover the virial theorem for bound orbits.

Orbit Radius

Virial Theorem for Circular Orbits:
TE = -KE = PE/2  |  KE = GMm/2r  |  PE = -GMm/r  |  TE = -GMm/2r
"More negative total energy = more tightly bound orbit"

Energy Bar Chart

KE = +GMm/2r
PE = -GMm/r
TE = -GMm/2r

Orbit Visualisation

Key Insights

As you increase r: KE decreases, PE increases (becomes less negative), TE increases (becomes less negative). The orbit becomes less tightly bound. At TE = 0, the object escapes.