From Kepler's law of periods,
T2∝R3
Therefore,
⇒(TBTA)2=(rBrA)3
⇒22=rB3rA3, ⇒rA3=4rB3
Two planets A and B of equal mass are having their period of revolutions TA and TB such that TA=2TB. These planets are revolving in the circular orbits of radii rA and rB respectively. Which out of the following would be the correct relationship of their orbits?
Held on 28 Jun 2022 · Verified 6 Jul 2026.
2rA2=rB3
rA3=2rB3
rA3=4rB3
TA2−TB2=GMπ2(rB3−4rA3)
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