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There are a lot of misconceptions out there and this a video about one of the most common ones.
So I went around asking people 'what makes the Moon go around the Earth?' and they told me..
The Earth puts a gravitational force on the moon But does the moon put a gravitational pull on the Earth?
Pull on the Earth yes. It does hence we have tides ETc the moon falls on the earth, [too] it affects like the tides and
women and yes
It [does] very powerful
does the moon pull on the Earth
probably that as well
Yeah
So what I want to know is
How does that force that the moon exerts on the Earth how does that compare in terms of size?
To the Force the Earth exerts on the moon
Well...
No scientist, but I think that one would be more powerful than that one
It's got a greater force coming from the Earth because it's greater mass is the Earth has more
Mass [cuz] it's a bigger mess. I thought greater mass is more [equals] more force [guys]
Does the moon pull on the earth?
Yes
But a lot less
Yeah, not as much as the Earth pulls on the moon.
Yeah
Yeah, but a little bit
not [very] strongly.
Yes
But much much much much smaller because if it's mass [less], [not] size
Because it's smaller. It's much smaller than [that] than the Earth
because it's smaller. This is small
Allow me to let you in on a little secret
Everyone got it wrong
The Force that attracts the moon to the Earth is exactly the same size as the force that attracts the Earth to the moon
So what's going on here? Why did everyone get it wrong?
Well, I think it comes down to cause and effect
The effect of the force on the moon is quite clear the moon goes in circles around the Earth
but the effect of that force on the Earth is
basically negligible; the Earth
barely wobbles at all So people interpret this
Negligible effect as
Indicating there's very little force affecting the Earth
But that is forgetting the third key piece of the puzzle which is inertia
Inertia is the tendency of Mass to Maintain State of motion
Since the Earth has a greater, mass
It has a greater, inertia and so even with the same amount of force on it
It doesn't accelerate that much now the funny thing [is] many of the [people] I interviewed
Could state Newton's third law which is every [force] has not equal and opposite reaction
Something about Newton's law doesn't seem to fit into that
[just] yet. You're good at this wait
Which Newton's law are we talking about the whole equal and opposite force thing?
Yeah, that one. So tell me what you're thinking man [ah] well
Did one would think that if you're into putting a force on me I would be putting an equal Force upon it
So why didn't they apply it to this problem?
Well, I think they may have memorized the words, but not really [believed] Newton's third law in their core
Did they really feel it in their spleen [I]?
Don't think they did so
Allow me to try to convince you, all of you spleen included, that Newton's third law really is true
Let's consider two objects
Initially they have the same Mass 1 kilogram each
So obviously the gravitational force of attraction must be the same on both of the objects
Now let's add a second kilogram to the first object
The Force on the second object will now be twice as great because that 1 kilogram is attracted
equally to each of the kilograms in the first object
But what is often forgotten is that new kilogram is
also
attracted to the second object meaning that the total force on each object is still the same they're attracted to each other with an
equal and opposite Force
We could add a third kilogram
And we would find the same thing the force on both objects is still the same
Even though the object on the left has [3] times the mass of the object on the right?
So we can see that no matter what the mass, any two objects will have the same gravitational force towards each other.
Can you feel Newton's third law in your spleen now? It should settle inside you and become a part of you