The earth’s radius is 6.37 x 10^6 m. Show with a calculation that the earth’s mass is 5.98 x 10^24 kg.
I've been trying to use F=G((m1*m2/r^2)) but it doesn't seem to be giving me the right answer... any help?
I've been trying to use F=G((m1*m2/r^2)) but it doesn't seem to be giving me the right answer... any help?
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The equation you are using won't give you the right answer because that is the equation for finding the gravitational force between two objects (the r is for distance between objects). I.e. the force of attraction between the Earth and the Moon.
An equation for solving the radius of a planet is:
r = sqrt (GM/a)
This can obviously be re-written and used to solve for mass (if you know radius).
Rewritten the equation becomes:
M = (r^2)(a)/G
r = Radius (in meters)
a = Acceleration due to gravity (9.8 m/s^2)
G = Gravitational Constant ( 6.6726e-11 N-m^2/kg^2)
M = Mass (in kilograms)
Cheers!
An equation for solving the radius of a planet is:
r = sqrt (GM/a)
This can obviously be re-written and used to solve for mass (if you know radius).
Rewritten the equation becomes:
M = (r^2)(a)/G
r = Radius (in meters)
a = Acceleration due to gravity (9.8 m/s^2)
G = Gravitational Constant ( 6.6726e-11 N-m^2/kg^2)
M = Mass (in kilograms)
Cheers!