A satellite of mass m moves in a circular orbit about Earth with speed v. What is its total mechanical energy?
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A satellite of mass m moves in a circular orbit about Earth with speed v. What is its total mechanical energy?

G1 Physics · Accepted Answer

Step 1: Circular orbital motion gives mv²/r=GMm/r², hence GMm/r=mv². Step 2: Total energy E=K+U=(1/2)mv²−GMm/r=(1/2)mv²−mv²=−(1/2)mv². Final answer: D — −(1/2)mv².