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Universal Law of Gravity Quiz
The Sun has a mass of 2x10
30
kg, and is 1.5x10
8
km away, while the mass of the Moon is 7.35x10
22
kg, and is 3.8x10
5
km away. Which exerts a stronger gravitational influence on the Earth.
The Sun
The Moon
They are about the same
Don't pick me!!
Cygnus X-1 is orbiting the massive star HDE226868, with a period of 5.6 days. What can you infer from this:
The mass of HDE226868.
The mass of Cygnus X-1.
Nothing.
The mass of the binary system.
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You Be the Astrophysicist
Cosmic Distance Scale
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Ask An Astrophysicist
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