Action Reaction

Why doesn't the weight force of a man standing on a floor form an action reaction pair with the force exerted by the floor on the man ?

#Mechanics

Easy Math Editor

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Comments

Normal force

David Stiff - 3 months, 1 week ago

Wait! Are you really Mr.David from Khan academy
If yes, I wanna thank you so much . You helped me a lot with physics. You're the best

Ahmed Sami - 3 months, 1 week ago

Oh, no, I'm not Mr. David. I'm not quite sure who that is, but I'm not affiliated with Khan Academy in any way! And as you can see, @Sathvik Acharya knows a lot more about physics than I do. :) But I'm glad Khan Academy is helping you. It's a great resource.

David Stiff - 3 months, 1 week ago

@David Stiff – 😅😅

Ahmed Sami - 3 months, 1 week ago

If body $A$ exerts a force $F_{AB}$ on body $B$ , then body $B$ will exert a force $F_{BA}$ on body $A$ such that $|F_{AB}|=|F_{BA}|$ and the two forces are opposite in direction. The two forces, $F_{AB}$ and $F_{BA}$ form an action reaction pair. This is essentially Newton's Third Law of Motion.

In the above scenario, the "weight force" of the man is the gravitational force , i.e force of earth on the man and normal force is due to force of floor on the man. Both forces act on the same body and hence do not form an action reaction pair.

Sathvik Acharya - 3 months, 1 week ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$