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06ps-02 Rollercoaster Design Solution

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    Well, let's see. Here another car just has potential energy.
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    Over here, it will also have potential energy because at the top of the loop,
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    the car is still some distance off the ground.
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    And so, what I'm doing here implicitly is using the ground as my zero point of potential energy.
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    Now, if this is a circular loop, this height is going to be 2R,
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    but it will also have some kinetic energy here.
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    So from an energy point of view, the potential energy up here is getting converted
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    to both potential energy and kinetic energy.
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    Let's set up that equation. Well, here is my equation expressing the conservation energy.
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    Potential energy goes to potential plus kinetic.
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    The mass is cancelled and remember I'm solving for the minimum height.
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    I'm going to set this velocity equal to the minimum possible velocity
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    that the car could have as it goes to this loop.
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    When I worked this out, I get a minimum height of 25 m.
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    If I make the first hill any lower than that, the car will not have enough energy
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    to make it safely run this loop and you might have some people falling out of the car,
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    which isn't the best idea when designing a roller coaster.
タイトル:
06ps-02 Rollercoaster Design Solution
Team:
Udacity
プロジェクト:
PH100 - Intro to Physics
Duration:
01:00
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