WEBVTT
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So the directory off the moon around the planet is
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not a perfect circle. It's rather something like on
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the lips like this one. So in this orbit
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there are two special distances the maximum distance between the
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satellite on the planet and the minimum distance between the
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satellite and the planet. Now, remember the following
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the gravitational force increases, as did the stents decreases
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. Therefore, the gravitational force will be bigger in
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this point then in these points. So here we
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have the biggest gravitational force. Let me call it
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F B. While here we have the smallest gravitational
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force. Let me call it F s. Then
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the problem says that the Rev additional force F B
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is 11% bigger than the reputational force. F s
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should be is equals to 1.11 times f s.
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Now, what is the relation between the maximum and
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the minimum distances? So remember the equation for the
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gravitational force. Magnitude after reputational force is equal student
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utan, constant time. The man times the mass
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number one times the mass number two divided by the
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distance between these masses squared. So what is the
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reputational force at the point? FB It's equals to
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the Newtown. Constant times the mass off the Earth
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times the mass off the moon divided by that minimum
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distance squared And on the other side what? We
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have 1.11 times the magnitude off this molesting gravitational force
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. Which is it? Costa G times the mass
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off the Earth times the mass off the moon divided
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by that maximum radios squared. Not that there are
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a lot off common terms on both sides, so
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we have a lot of simplifications. G is the
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same. The minds off the earth is the same
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. The mask off the moon is the same,
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so we're left. If the following one divided by
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the minimal radios squared is equal to 1.11 divided by
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the maximum radios squared. Then we can send the
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maximum radios squared to the other side, multiplying to
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get our marks squared. Divided by arming. Squared
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is he goes to 1.11 taken the square it off
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both sides of the equation. We got our much
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divided by army. Is it close to the square
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root off 1.11 which gives us a ratio off approximately
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one 0.5 So the maximum radios this one is only
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5% bigger than the minimum radius. These one in
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the situation