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08-25 What About Energy?

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    Well, we've already learned a lot about electricity.
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    We know that negative charges like to be with positive charges.
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    We know four methods to charge an object,
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    and we've learned that the earth is both a source and a sink for electrons.
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    But one thing we haven't talked about at all—
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    one of the most important concepts in physics is energy.
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    Why don't we go back to Professor Fregonese and see what he has to say
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    about energy as it relates to electricity.
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    One of the most evident effects of electricity are attractions and repulsions
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    of electrified bodies and this is important because you can use these forces
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    to produce work, to produce energy.
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    We can start understanding it with an analogy with gravity, which is simple
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    because we have only attraction and electricity is much more complicated because
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    you have also this complication of repulsion.
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    If I have a body of mass, there is an attraction between the body and the earth
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    and there is potential energy.
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    If I drop this body, it has the capacity to produce some work
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    maybe to break a neck down there.
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    It goes down and the potential energy diminishes
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    and it acquires kinetic energy, movement, velocity,
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    and which is proportionate to the square of velocity.
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    With electricity, it's more complicated because of repulsion but the idea is similar.
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    You can use the interactions between electrified borders between charges
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    to produce work so to have energy to produce something.
Title:
08-25 What About Energy?
Team:
Udacity
Project:
PH100 - Intro to Physics
Duration:
01:39
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