GR0177-22 Need More Detailed Explaination
Posted: Sat Oct 21, 2006 7:01 am
Okay guys. I read Yosofun's solution but it seems like one has more variables than equations to solve for velocity, period, and mass of the planet.
I know (E) is automatically eliminated since semimajor axis is the same as maximum distance.
But Kepler's Third Law States
T^3 = (4 * pi^2/GM) * r^2
You you NEED M the mass of the planet to solve for T the period.
You also NEED M the mass of the planet to solve for v the minimum speed using the conversation of energy:
-k/(2a)=1/2mv^2-k/r
where k = GMm/r
It seems we have three unknown variables T, M, v and only two equations.
Am I missing something??
I know (E) is automatically eliminated since semimajor axis is the same as maximum distance.
But Kepler's Third Law States
T^3 = (4 * pi^2/GM) * r^2
You you NEED M the mass of the planet to solve for T the period.
You also NEED M the mass of the planet to solve for v the minimum speed using the conversation of energy:
-k/(2a)=1/2mv^2-k/r
where k = GMm/r
It seems we have three unknown variables T, M, v and only two equations.
Am I missing something??