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whoareyou

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## Homework Statement

Hello, I need somebody to double check and confirm my answer. I have absolutely no idea what the solution manual is doing.

Moon effect. Some people believe that the Moon controls

their activities. If the Moon moves from being directly on the

opposite side of Earth from you to being directly overhead, by

what percent does (a) the Moon’s gravitational pull on you

increase and (b) your weight (as measured on a scale) decrease?

Assume that the Earth–Moon (center-to-center) distance is

3.82 x 10^8 m and Earth’s radius is 6.37 x 10^6 m.

## Homework Equations

Newton's Gravitation Equation(s)

## The Attempt at a Solution

I got the first part of the question using a percent increase formula. I got 6.9% which is what the solution manual got. However for part b), I have no idea what they are doing. I'll attach their work below. What I did was used the percent increase formula again (absolute value since its a decrease) got the answer to be

**0.000685%**. This is by using free body diagrams (ie. the case where the moon is on the opposite side of the earth, both the Earth's gravity and the gravity from the moon act in the same direction and in the case where the moon is on the same side, it would be the Earth's gravity minus the moon's gravity.)

Solution manual: