Compared to the strength of the Earth’s gravity at its surface where r = Re and Re is the radius of the Earth, how much weaker is gravity at a distance of 5Re?  15Re?

We would like to be able to make meaningful interpretations of variations in the acceleration due to gravity, g, as small as 0.1 mgal. How accurate must our knowledge of the latitude of our gravity stations be? (A “gravity station" is just a location at which you make a gravity measurement.) You can assume your latitude is 45°.

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Let the radius of the Earth be R, and we approximate the Earth as a sphere. In order for an object to glide along the equator of the Earth at sea level, what is the speed at which it needs to be moving? gR gR VgR O (gR)?

NEE HELP PLS

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The density of Planet Y in the previous problem is Show the entire calculation. Calculation: The universal gravitational -11 3 -1 -2 constant is 6.67430*10 m kg s . Planet Y has a radius of 5360km or 5.360*10 m and a mass of 4.56*10²3 kg. On this planet, a rock falls vertically down from a cliff overhang to the ground. The height of the cliff is 86m. The time it M takes the rock to fall from the overhang to the ground is Show the entire calculation. Calculation: g = G*- The density O R of Planet Y in the previous problem is Show the entire calculation. Calculation:

11 Astronomical observations of our Milky Way galaxy indicate that it has a mass of about 8.0 x 10- solar masses. A star orbiting near the galaxy's periphery is 5.9 x 10" light-years from its center. (a) What should the orbital period (in y) of that star be? y. (b) If its period is 6.1 x 10' years instead, what is the mass (in solar masses) of the galaxy? Such calculations are used to imply the existence of other matter, such as a very massive black hole at the center of the Milky Way. solar masses