1) Your weight is due to the gravitational attraction of the Earth. The Moon, though, also exerts a gravitational force on you, and when it is overhead, your weight decreases by a small amount. Calculate the effect of the Moon on your weight. Express your result as a percentage difference for the cases of the Moon overhead and the Moon on the opposite side of the Earth.


2) The tides on the Earth are due to the variation of the Moon's gravitational force with distance. Find the approximate ratio of the Moon's gravitational force on two portions of the ocean, one nearest the Moon and one on the opposite side of the Earth.


3) In our derivation of Kepler's laws, we assumed the only force on a planet is due to the Sun. In a real solar system, however, the gravitational forces from the other planets can sometimes be important. Calculate the gravitational force of Jupiter on the Earth. Do the calculations for the cases when Jupiter is both closest (Fc) to and farthest (Ff) from the Earth (see the figure below). (The properties of several objects in the solar system are given in the table below.)


50fg per correct answer

All three problems make use of the equation:

Fg = G*m1m2/r^2

G = gravitational constant
m1 = mass of you
m2 = mass of object pulling on you
r = distance between you AND THE CENTER of the object pulling on you

All you need to know is masses and distances.

Since all you need is ratios, your mass is irrelevant.

You only need the masses of each, and the respective distances from the point of interest to the center of the main gravity bodies for each relation.

Also, we must have the table for problem 3 if you expect us to do it.

This post was edited by Dontrunaway on Oct 3 2013 09:59pm