## 09-19 Time Dilation

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So with this effect but I haven given a name to yet but we're going to call time dilation.
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You'll see why in a minute and we have these equations relating
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the rates at which different clocks tick.
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And actually this number v/c--I'm going to stop writing v/c.
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Instead I'm going to use this number or variable β to represent the ratio of
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a frame's speed to the speed of light and the variance are polishing things up,
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let's go one step further and instead of writing t‘ like this, lets put the t out
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and give this quantity in parenthesis its own name and the name I'm going to give--
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well, we've seen the α and β, it's time for the next Greek letter, is γ.
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So now, our complicated equation becomes t'=γt.
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So actually we want to understand what's going on here. We need to understand γ a little better.
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So first let me tell you without giving you much proof and I'm sorry for doing it
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that v the speed that we can move or about a frame of reference can move--
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well it has an upper bound--it can't go any faster than c, can't go faster than the speed of light.
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So we can go with the slowest 0 stop or up to the speed of light
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which means that β is between 0 and 1.
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That can't be equal to the speed of light.
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I want you to tell me what's the minimum and maximum value for γ.
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So for γ min, it's the lowest possible value of γ as it is low as we want.
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Can it go to a negative or billion--it's the lowest possible value 0 or is the lowest possible value 1.
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Likewise, for γ max, it's the highest possible value that γ can be.
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Is it 1, 2 or can γ max grow as large as we want.
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So that's two questions. Select the best answer for each.
タイトル：
09-19 Time Dilation
Video Language:
English
Team:
Udacity
プロジェクト：
PH100 - Intro to Physics
Duration:
01:34