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PrometheuSIT
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Homework Statement
Planet Z is 5000 km in diameter. The free-fall acceleration on Planet Z is 7.00 m/s^2. What is the mass of Planet Z?
Homework Equations
Well Newton's gravitational law G(M1M2)/R^2
And I cannot think of much else
The Attempt at a Solution
On one of the earlier homeworks we were given a table in which there were fictional planets and their ratios of mass and radius to Earth so I tried using
gG M(earth)/(R(earth))^2 = gG M(z)/(R(z))^2
Where the "g"s are each planet's free fall acceleration.
so that the Gravitational constant would cancel and I'd have the Mass of planet Z
For the mass of the Earth I used 5.97E34, for the radius of the Earth I used 6387.1 km
I know that the radius needs to be in meters and would be correctly notated as 6.3871E6
I don't know how to figure this one out