Gravity on mass on earth's surface vs sun-earth gravity

AI Thread Summary
The discussion revolves around calculating the gravitational force exerted by the sun and the moon on a 5.000 kg mass on Earth's surface during a solar eclipse. The gravitational force from the moon, Fm, is correctly identified as mg, where g is 9.8 m/s². The gravitational force from the sun, Fs, is derived using the formula (mass of the sun)(mass of the object)/(distance from the sun to the object)². Participants clarify that the focus is on the ratio of these two forces, Fs/Fm, rather than the force of attraction to Earth itself. The conversation highlights the importance of understanding gravitational interactions in this context.
ninjagowoowoo
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Q:
A mass of 5.000 kg is sitting on the Earth's surface directly under the sun during a solar eclipse. The sun exerts a gravitational force with magnitude Fs on the mass. The moon's gravitational force on the mass has magnitude Fm. Calculate the ratio Fs / Fm.

This problem is really frustrating me. For the object, wouldn't Fm be mg = 5*9.8?

Then wouldn't the Fs be (mass of the sun)(mass of earth)/R^2 ?

So wouldn't it be the Fs divided by Fm? Please help??!
 
Physics news on Phys.org
You are being asked to calculate the ratio of the forces of attraction to the sun and to the moon for a mass that is at the surface of the earth. You are not asked for the force of attraction to the earth.
 
HAH wow I'm embarassed... thanks :blushing:
 
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