## 10x-15 Gravity and Electricity

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This question is about both gravity and electricity.
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Let's say that Benjamin Franklin is standing in a room holding an object.
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This room actually has a horizontal electric field.
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That electric field is equal to 100 N/C.
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Obviously, Ben Franklin is very excited, because he gets to do an experiment with electricity.
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Furthermore, let's say that this ball has both a mass, 8 kg,
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and it's actually charged as well.
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It's charge is 0.1 C. That's a positive charge.
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Now what's going to happen when he releases this ball is it will feel two forces.
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It will, of course, feel a force from gravity downward,
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but it's also going to feel an electric force.
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It's going to undergo 2-dimensional motion,
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but this will be much different than the 2-dimensional motion of a ball being thrown
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in the air under normal circumstances,
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because now there's going to be a horizontal component of acceleration.
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I want you to tell me if this height is equal to 1.2 m
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and we know that the ball will feel a force over here
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so it'll probably land somewhere--I don't know--here or here or here.
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I want you to tell me d--the distance away from Ben Franklin
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where the ball strikes the ground.
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I'm warning you this is quite a tricky question,
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but using what you know about F = ma and motion and electricity
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you can tie it all together, and I believe you can get this answer. Give it a shot.
Cím:
10x-15 Gravity and Electricity
Video Language:
English
Team:
Udacity
Projekt:
PH100 - Intro to Physics
Duration:
01:26