Showing Revision 1 created 07/23/2012 by Amara Bot.

1. Title:
   07-58 Finding Simple Harmonic Motion
2. Description:

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   Okay, let's see. We want a period of 1 second.
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   Let's convert this to an angular frequency ω using this equation.
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   So, we want an angular frequency of 2π, an I know that ω²
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   is equal to whatever this thing is, the minus something times x.
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   In this case, ω² is equal to g/L. Let's solve this for L.
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   This gives me a length of 0.25 meters.
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   Now, it turns out that for pendulum clocks, actually, we might want a period of 2 seconds.
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    The reason is because let's say we had a pendulum with a period of 1 second.
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    That means that it takes 1 second for when I pull it back to go
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    over here and then all the way back.
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    That's actually quite a bit of motion and a period of 2 seconds is actually a little bit better,
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    because then every time the pendulum reaches one if its extrema,
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    either all the way over here or all the way over there,
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    we know 1 second has passed--half of the period.
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    I wonder what would be the period for a 2-second pendulum.
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    Why don't ask Tjeerd the clockmaker what he thinks.
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    [Tjeerd ] When you design a pendulum or pendulum clock,
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    the thing that mostly influences the period of oscillation is the length of the your pendulum.
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    If you have an ideal pendulum, a fictional pendulum,
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    made out of no materials as a mathematical piece,
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    the pendulum of a second, oscillating in a second,
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    will have a length of about a meter.
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    A pendulum is made out of materials, and the rod, for instance, is made out of steel or brass,
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    which brings the center of oscillation up.
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    That's why you need a heavy pendulum bulb underneath the pendulum--
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    to bring the center of gravity in the pendulum down
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    to have your proper theoretical length.