WEBVTT

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Hey there. How's it going? Oh, I'm just
struggling with a video idea for NASA.

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Hey, whatcha got here, an apple? Yeah. It's a good study snack. I'm trying to read up

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on Newton's first law, but something
doesn't quite make sense.

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I thought an object at rest doesn't have
any forces acting on it. See, that's a

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common misconception, but I have a way of explaining it.

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So we can use this apple

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to explain Newton's first law. Look at
how the apple moves.

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You see here the apple fell towards the ground. That is gravity and it keeps you on this Earth.

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Now look at the apple again on the table.
It isn't moving right now but gravity

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is still acting on it. This is Newton's
first law where there isn't only gravity

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acting on the apple, but there is a force
from the table keeping the apple

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stationary. This brings up the first
thing to always keep in mind when you're

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looking at forces. They always come in
pairs.

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Hey, thanks for explaining that.

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So forces are just properties of objects
right? Actually that is also a

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misconception. Wait, narrator, what are you doing here? I'm here to explain that

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forces are just interactions. Here let me
show you.

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An apple cannot become a force unless
something else applies an acceleration

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to it. The Earth's pole gives a
gravitational force, the desk gives the

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apple a normal force resisting Earth's
gravity, and the bat applies a force on

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the apple giving an applied force. Even
though the table may give the apple a

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friction force resisting the apple's
applied force, the friction force is

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overwhelmed by the apple's applied force,
which results in a net force in the

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applied force direction -- which causes the apple to go in the direction of the

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applied force.  This causes the apple to have motion

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since it has an initial starting point, a
direction it is going to, and how far

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in force it will go, called magnitude.

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Wow, thanks for going out of your way to get this narrator and scientist to explain to me how forces work.

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Anytime.