Newton's Third Law of Motion.

Instead of posting links and quotes just google the title, it will be worth it to see other perspectives and how it effects nature.

I am primarily interested in examples that may go beyond motion and how it is true for other forces or objects. Does everything have an equal and opposite?

We can look at the obvious male\female, good\bad, happiness\sadness, day\night etc.

Posted in General Philosophy so as not to discuss the "Law of Motion" itself but to see how it is evident in other things. Where is this not true in other aspects of life?

I am primarily interested in examples that may go beyond motion and how it is true for other forces or objects. Does everything have an equal and opposite?
The clue may be in the name: Newton's Third Law of Motion.


We can look at the obvious man\woman, good\bad, happiness\sadness, day\night etc.
How are these "equal and opposite"?


Posted in General Philosophy so as not to discuss the "Law of Motion" itself but to see how it is evident in other things.
No, you appear to be claiming that it's evident. This has yet to be established.


Where is this not true in other aspects of life?
Most of reality? :shrug:

Posted in General Philosophy so as not to discuss the "Law of Motion" itself but to see how it is evident in other things. Where is this not true in other aspects of life?

huh?

Try to explain this a bit better please.
As it stands, I cannot see how I can leave this thread in Philosophy....

huh?

Try to explain this a bit better please.
As it stands, I cannot see how I can leave this thread in Philosophy....

This is going to take some time. Leave it here for two days, I cant respond right now.

This is going to take some time. Leave it here for two days, I cant respond right now.

Fair enough.

I just can't see how you propose to discuss a physics concept outside of that context....

Newton's Third Law of Motion.

Instead of posting links and quotes just google the title, it will be worth it to see other perspectives and how it effects nature.

So you're asking people to go away and research Newton's third law of motion for themselves, rather than telling them anything about the topic of your thread. What a waste of time.


I am primarily interested in examples that may go beyond motion and how it is true for other forces or objects. Does everything have an equal and opposite?

Newton's law concerns only forces. It has no application ot "everything".

But, the answer is "No". Not everything has an equal or an opposite. Examples: what's the equal of a banana? What's the opposite of Friday?


We can look at the obvious male\female, good\bad, happiness\sadness, day\night etc.

What's equal about happinesss and sadness?


This is going to take some time. Leave it here for two days, I cant respond right now.

Then you should have posted your thread in two days time.

Stopping wasting everybody's time.

John99,

You know, after giving this some thought, although I'm admittedly guessing, I'm wondering if perhaps you're simply talking about the notion of reciprocity, in very general terms. The idea that some behaviour in turn is seen as 'causing' an other directed towards the precedent....

In which case.. we're not even talking about Newton's Third Law then.....


...dunno...

That's been raised (in passing) more than once over the years (including the spurious reference to Newton) by various posters. But no one, until now, (if that is indeed John's premise) has done anything more than vaguely wave their hand in its direction and then move on.

That's been raised (in passing) more than once over the years (including the spurious reference to Newton) by various posters. But no one, until now, (if that is indeed John's premise) has done anything more than vaguely wave their hand in its direction and then move on.

Indeed.

I've often been confused as to how some people think they can grab on to some principle or law of, say, physics, and feel like it's perfectly reasonable to extrapolate its application beyond its intended scope...

odd.

I'm wondering if perhaps you're simply talking about the notion of reciprocity, in very general terms. The idea that some behaviour in turn is seen as 'causing' an other directed towards the precedent....

You mean like karma?

You mean like karma?

hehe

That's what I was (guessing) thinking of....

" What's the opposite of Friday?"

Friday is made up by humans.

Strength - Weakness

Hot - Cold

Ok, John. What's the opposite of grass? Grass isn't made up by humans, is it?

And what's the equal of banana? Banana isn't made up by humans, is it?

And what's the opposite of good poetry? Oh, wait. That's made up by humans, so it can't have an opposite.

Ok, John. What's the opposite of grass? Grass isn't made up by humans, is it?

And what's the equal of banana? Banana isn't made up by humans, is it?

.

I thought about that. They come from the dirt, the opposite of dirt is water.

I guess this deals with high level and we trace things back we always find the equal and it seems like the opposite: Positive and negative, life and death, horizontal and vertical, open and closed, light and dark.

Dirt is the opposite of water? This is just ridiculous now. You are always going to end up with insurmountable logical difficulties when you try to apply a physical law that relates to a specific phenomena to anything and everything in the physical universe.

Besides, you're not even talking about reactions anymore, unless you are saying that dirt is a reaction to water (which is even more ridiculous).

Newton's Third Law of Motion.

Instead of posting links and quotes just google the title, it will be worth it to see other perspectives and how it effects nature.

I am primarily interested in examples that may go beyond motion and how it is true for other forces or objects.

In physics, there's statics as well as dynamics. If you go over to the wall and press your hands against it, it will effectively push back against you with equal force and your hands will feel pressure as a result. But nothing's moving. So it isn't always motion.


Does everything have an equal and opposite?

We can look at the obvious male\female, good\bad, happiness\sadness, day\night etc.

Posted in General Philosophy so as not to discuss the "Law of Motion" itself but to see how it is evident in other things. Where is this not true in other aspects of life?

You seem to be getting at an idea that's a lot older and more general than Newton. It's a metaphysical idea more than it's a physical one. In today's philosophical style, it's more about logic and linguistics.

I'm thinking of the old Ionian idea of 'apeiron'. The Greek word literally means 'unbounded' (without perimeter), and Anaximander seems to have used it to mean 'formless'.

The idea here is of a basic formless... stuff, the idea (ancient even in the time of the Greeks) of primeval chaos, imagined as pure being. This original 'arche' (out-of) becomes the endless variety of particular things that we experience through the imposition of... shapes, boundaries, outlines... upon it.

So every individual thing that comes into existence as the result of the imposition of a particular form, divides reality (imagined as formless matter) into an 'inside' and an 'outside', into what each particular thing is and everything else that it isn't.

We still see philosophers proposing ideas like that, for example when it's suggested that words acquire at least part of their meaning by what they exclude. In order to know what X means, we have to have some idea of what ~X means as well, we have to have some idea what it means to not be X. It's often argued that the ideas of what something is and what it isn't go together and are inseparable.

But, the answer is "No". Not everything has an equal or an opposite. Examples: what's the equal of a banana? What's the opposite of Friday?The equal of a banana is a mango. Everyone knows that.
And as for Friday's opposite... that would clearly be Tuesday afternoon at 3:15pm, but only on a wet and miserable March day when people forget your birthday :(. It is the opposite of all the Friday's in the year.

Surely everyone knows these??

:shrug:

yin-yang ? http://t1.gstatic.com/images?q=tbn:ANd9GcS4yv4Kr10dWfJW-6qC8OnlSB8rwZxDVZQJ5XUKXoZ6niZiEhh3mA

" What's the opposite of Friday?"

Friday is made up by humans.
Aren't "good" and "bad" made up by humans?


Strength - Weakness
Hot - Cold
These aren't opposites: weakness is a lack of strength just as cold is the absence of heat.

What's the opposite of a worthwhile thread with a rational premise?

Ok, John. What's the opposite of grass?
Busted? :shrug:

Ok, John. What's the opposite of grass?

Weed? :m: :)

I thought about that. They come from the dirt, the opposite of dirt is water.

I guess this deals with high level and we trace things back we always find the equal and it seems like the opposite: Positive and negative, life and death, horizontal and vertical, open and closed, light and dark.

James pointed out the error in your thinking.
You're extrapolating human created notions of organization beyond their proper scope...

This is going to take some time. Leave it here for two days, I cant respond right now.
So much for that...

You know...after some reflection i conclude that equal and opposite is not accurate. In fact i dont think the opposite\opposing is ever equal.

Here is an example for simplification:

You stand in a body of water, the objective is to push an object that his half submerged. You exert X amount of energy\force to push the object...but the question is: We know what the opposite reaction is but where is it equal?

See, i think throughout this thread people are making this mistake. They view equal and opposite in conjunction. This is psychological conditioning.

So now we eliminate equal and concentrate on opposite, though if you find what you feel as an equal feel free to post it.

yin-yang ? http://t1.gstatic.com/images?q=tbn:ANd9GcS4yv4Kr10dWfJW-6qC8OnlSB8rwZxDVZQJ5XUKXoZ6niZiEhh3mA

Nah, not interesting in it.

You know...after some reflection i conclude that equal and opposite is not accurate. In fact i dont think the opposite\opposing is ever equal.
Do you mean as far as Newton is concerned?


See, i think throughout this thread people are making this mistake.
Correction: the mistake was yours on the original premise.


They view equal and opposite in conjunction. This is psychological conditioning.
Incorrect: with regard to Newton it's a scientific fact.


So now we eliminate equal and concentrate on opposite, though if you find what you feel as an equal feel free to post it.
In other words this thread is, as usual from you, a waste of time...

John99:


You know...after some reflection i conclude that equal and opposite is not accurate. In fact i dont think the opposite\opposing is ever equal.

Here is an example for simplification:

You stand in a body of water, the objective is to push an object that his half submerged. You exert X amount of energy\force to push the object...but the question is: We know what the opposite reaction is but where is it equal?

Where isn't it equal? Explain.

Give an example of Newton's Third Law of Motion.

Give an example of Newton's Third Law of Motion.
Yeah right:

Newton's Third Law of Motion.
Instead of posting links and quotes just google the title, it will be worth it to see other perspectives and how it effects nature.
Since you couldn't be bothered to explain how you understood it in the OP I'll leave it up to you to bring yourself up to speed.
I assumed (perhaps falsely) that you were actually familiar with the concept.
Is this going to be yet another of your totally inept refusals to see reality?

Attack the post not the poster. All i asked for were examples because every examlpe i give gets negative responses...so must be something wrong.

Attack the post not the poster. All i asked for were examples because every examlpe i give gets negative responses...so must be something wrong.
You've given one example: and James R has asked you a question. Which you have failed to answer at all.
How about a billiard ball striking another? Is that simple enough for you?

Give an example of Newton's Third Law of Motion.

How about you have the courtesy to answer the question I asked you first? It's in post #27.

Ok. In anticipation of your courtesy and honesty in answering my question to the best of you ability, I will answer yours in advance.

An example of Newton's third law of motion:

I exert a downwards force on my chair when I sit on it. The chair exerts an equal force upwards on me.

Dirt is the opposite of water?

oh yes, absolutely. Land | Sea

Here is another: High and Low

I exert a downwards force on my chair when I sit on it. The chair exerts an equal force upwards on me.

Not exactly.

Not exactly.
What do you mean "not exactly"?
The forces aren't exactly opposite or that isn't exactly what happens?

His weight is pushing down but the seat is not pushing up and they are not equal either.

Unless his chair has a spring. What kind of chair is this?

Trolling again, John?
For your sake, I hope so..

Give an example of Newton's Third Law of Motion.

The recoil from a shotgun.

oh yes, absolutely. Land | SeaSo where does "air" fit into it?

Okay - what is the opposite side of one side of an equilateral triangle?

The recoil from a shotgun.

Yes.

So where does "air" fit into it?


Do you mean oxygen?

Do you mean oxygen?No, I mean "air" - in the same way that you referenced "land" and "sea".

And the opposite side to one of the sides of an equilatral triangle? :shrug:

His weight is pushing down but the seat is not pushing up and they are not equal either.
I see you're as ignorant of Newton (and forces) as you are of gravity and efficiency.
What sort arrogance (or blindness) does it require to make such statements when you obviously have no idea what you're talking about?

If the seat does not push back why does James not continue to move downwards? What stops him at the seat?

And the opposite side to one of the sides of an equilatral triangle? :shrug:
What's the opposite of "triangle"?

The opposite of fish? Pie.
Meat? Potatoes.
Indian? Chinese.
Tea? Is that coffee or lunch?
White? Yolk.
Opposite of 13? 46. At least on my street.
Sideways is a difficult one though...

No, I mean "air" - in the same way that you referenced "land" and "sea".


I only referenced it after i sadi: Dirt (soil) and Water. I am sure you knew that.


And the opposite side to one of the sides of an equilatral triangle? :shrug:

We can figure it out, many of these things are subjective, until you reach a certain level of understanding of that particular object.

I only referenced it after i sadi: Dirt (soil) and Water. I am sure you knew that.
Doesn't answer the question.


We can figure it out, many of these things are subjective, until you reach a certain level of understanding of that particular object.
And another side step.

Are you going to address ANY of the points raised?

Newton's Third Law of Motion.

Instead of posting links and quotes just google the title, it will be worth it to see other perspectives and how it effects nature.

I am primarily interested in examples that may go beyond motion and how it is true for other forces or objects. Does everything have an equal and opposite?

We can look at the obvious male\female, good\bad, happiness\sadness, day\night etc.

Posted in General Philosophy so as not to discuss the "Law of Motion" itself but to see how it is evident in other things. Where is this not true in other aspects of life?

That seems to imply that the only way I can be happy is to exert an equal yet opposite emotion upon someone else.

As in, in order for me to be happy I have to make someone else feel like crap.

While some people can become happy by doing that, its definitely not a prerequisite.

Just because they both exist does not mean they need to be experienced equally.

I'll ask again:

If the seat does not push back why does James not continue to move downwards? What stops him at the seat?

I'll ask again:

That isnt what is happening. It is an incorrect application of the third law of motion.

Then all physics courses are taught wrong.

What stops a rock that falls to the ground? Hint: It's not that gravity stops pulling.

That isnt what is happening.
You keep saying that. And you've yet to explain what does happen (in your own little world).


It is an incorrect application of the third law of motion.
False.
It is a correct application.
If you don't think so then lay out for us what (you think) Newton's third law means, and how (and where) it applies.

So far all you've done is dodge, side step and avoid while saying "that's not how it works".

The equal of a banana is a mango. Everyone knows that.
And as for Friday's opposite... that would clearly be Tuesday afternoon at 3:15pm, but only on a wet and miserable March day when people forget your birthday :(. It is the opposite of all the Friday's in the year.

Surely everyone knows these??

:shrug:
I did . I knew it . Another Banana is equal to a Banana too. It is the economic system that controls human activity. We are slaves to it . Oh and Tuesday comes from a god name Tioso ? Can't remember how to spell ? It is a god though. Tuesday is a god

Oh and Tuesday comes from a god name Tioso ? Can't remember how to spell ? It is a god though. Tuesday is a god
In English all of the days of the week (except Monday = Moon Day and Sun day) are named after gods.
Saturday still remains Roman: Saturn's Day, and the rest are Norse/ Old English, Tiw (Tyr), Woden (Odin), Thor and Frigga (Freya).

Then all physics courses are taught wrong.


oh...that is some statement to make. It's a wrong statement. The thread is either you know it or you dont. These things take time.

Right. So if superman is standing in front of a car with his hands on the grill preventing it from moving forward, he's not pushing back because he's stationary?

oh...that is some statement to make. It's a wrong statement.
Wrong.
If you are right then all physics courses that teach Newton's Third Law (and all the applications of it in actual use) are wrong.


The thread is either you know it or you dont.
And you apparently don't.


These things take time.
As long as getting a straight answer out of you?

Right. So if superman is standing in front of a car with his hands on the grill preventing it from moving forward, he's not pushing back because he's stationary?

This is why i specifically recommended that people brush up on this:

http://en.wikipedia.org/wiki/Newton's_laws_of_motion

Read the whole page, Rav.

This is why i specifically recommended that people brush up on this:
You in particular.
You display as much understanding that page as you have previously of efficiency and gravity.

This is why i specifically recommended that people brush up on this:

http://en.wikipedia.org/wiki/Newton's_laws_of_motion

Read the whole page, Rav.

I think you're going to have to highlight the specific section that you think refutes what is being explained to you here, because that Wikipedia page is perfectly consistent (as you would expect it to be).

I think you're going to have to highlight the specific section that you think refutes what is being explained to you here, because that Wikipedia page is perfectly consistent (as you would expect it to be).

We are talking about the chair example. What you understand or dont understand is not my responsibility.

We are talking about the chair example. What you understand or dont is not my responsibility.

And you seem to be saying that the chair isn't pushing back, which is a ridiculous assertion for someone who claims to have read and understood the Wikipedia page you linked to.

What you understand or dont understand is not my responsibility.
YOU made the claim that the chair example is a misapplication. It is up to you to show why you believe so, especially since physics, and physicists (and engineers) agree that the application is 100% correct.
You're just stalling again.

So far it's evident that any misunderstanding is purely yours. And now you're adding evasiveness bordering on dishonesty to that.

And you seem to be saying that the chair isn't pushing back, which is a ridiculous assertion for someone who claims to have read and understood the Wikipedia page you linked to.

I know the chair is not doing this:

http://upload.wikimedia.org/wikipedia/commons/b/b2/Skaters_showing_newtons_third_law.svg

One force acting upon another. With the chair example it is only one force pushing one way. Just like pushing against a brick wall...the force can only go one way, once the force exceeds a specific point the wall breaks.

Notice in the image above the force goes both ways...so the chair is not, in reality, pushing back but accepting the force. This is a common mistake vis-à-vis Newtons Third Law of Motion.

Maybe you should start with something a little easier than Wikipedia: http://www.physicsclassroom.com/class/newtlaws/u2l4a.cfm

(remember to do the exercises at the bottom!)

I know the chair is not doing this
No, you believe it isn't.
Incorrectly.


One force acting upon another. With the chair example it is only one force pushing one way. Just like pushing against a brick wall...the force can only go one way, once the force exceeds a specific point the wall breaks.
Also wrong.


Notice in the image above the force goes both ways...so the chair is not, in reality, pushing back but accepting the force. This is a common mistake vis-à-vis Newtons Third Law of Motion.
Wrong.
The only mistake here is yours.

From your own link

The Third Law means that all forces are interactions between different bodies,[31] and thus that there is no such thing as a unidirectional force or a force that acts on only one body. If body A exerts a force on body B, body B simultaneously exerts a force of the same magnitude on body A— both forces acting along the same line.

Maybe you should start with something a little easier than Wikipedia: http://www.physicsclassroom.com/class/newtlaws/u2l4a.cfm

(remember to do the exercises at the bottom!)

You googled the same keywords i did...i already saw that.

http://www.schools.utah.gov/CURR/Science/sciber00/8th/forces/sciber/newton3.htm

http://hyperphysics.phy-astr.gsu.edu/hbase/newt.html

Without specifying the nature or origin of the forces on the two masses, Newton's 3rd law states that if they arise from the two masses themselves, they must be equal in magnitude but opposite in direction so that no net force arises from purely internal forces.

When you are sitting on a chair, your weight is a force pushing down on the chair.
It is not obvious that there is an equal force from the chair pushing upwards against you.
Newton's First Law says that there must be one because the forces on a stationary object (yourself) must be balanced.

If the force of your weight on the chair did not have an equal opposing force,
then the forces on you would be unbalanced and you would accelerate downwards.

Another example would be staying still while pushing against a wall.
The wall must be pushing back against you with an equal force otherwise the wall would accelerate away from your hand.
http://www.gcsescience.com/pfm17.htm

Note that this is GCSE (14-16 year-old schooling) science.
Maybe you slept through those years. :rolleyes:

You googled the same keywords i did...i already saw that.

Oops. Busted! I was hoping to keep the fact that I do google searches a secret around here.

Even funnier than that is the fact that you keep posting links that clearly prove yourself wrong.

Oops. Busted! I was hoping to keep the fact that I do google searches a secret around here.


One step ahead of you, Rav...

One step ahead of you, Rav...

Certainly not in the basic physics department (and obviously not in the humour department either).

Certainly not in the basic physics department (and obviously not in the humour department either).

Well these things are debatable.

Well these things are debatable.
No they aren't.
You're incorrect. And unwilling (or unable) to see it.
You have been shown to be wrong, even from your own source, and persist in your misunderstanding.
Rav (not that he needs me to say) is correct and understands it. You are not and don't.

Rav, take a look at this:

"Examples of common misunderstandings
Newton's third law is frequently stated in a simplistic but incomplete or incorrect manner through statements such as
Action and reaction are equal and opposite
To every action there is an equal and opposite reaction

These statements fail to make it clear that the action and reaction apply to different bodies. Also, it is not because two forces happen to be equal in magnitude and opposite in direction that they automatically form an action-reaction pair in the sense of Newton's Third Law.
Action and reaction are often confused with the issue of equilibrium. For example, consider the following statement:
A book standing still on a table is at rest because its weight, a force pulling it downwards, is balanced by the equal and opposite reaction of the table, a force pushing it upwards.

This statement is misleading in that it suggests that the force exerted by the table on the book is the reaction associated with the book's weight. This is not the case, since the two forces are different in nature and are both applied to the book; one cannot be the reaction to the other, since they must apply to different bodies. In fact the force exerted by the table can be seen as the reaction to the contact force exerted by the book on the table, which in turn is equal to the book's weight."

http://en.wikipedia.org/wiki/Reaction_(physics)#Examples_of_common_misunderstan dings

Which does nothing whatsoever to support your claim.
You're flailing in an effort to cover your ignorance.

This statement is misleading in that it suggests that the force exerted by the table on the book is the reaction associated with the book's weight. This is not the case, since the two forces are different in nature and are both applied to the book; one cannot be the reaction to the other, since they must apply to different bodies. In fact the force exerted by the table can be seen as the reaction to the contact force exerted by the book on the table, which in turn is equal to the book's weight."

How is this supposed to refute the fact that my chair is exerting a force on my arse (just like the table is exerting a force on the book)?

How is this supposed to refute the fact that my chair is exerting a force on my arse (just like the table is exerting a force on the book)?
Isn't it obvious?
It refutes the claim because because John doesn't have clue what it means and he hopes no-one else does.
Therefore he must be right if we don't understand it.

Does everything have an equal and opposite?
No.

How about you have the courtesy to answer the question I asked you first? It's in post #27.



An excellent point.

John99,

You have nothing to say on this?

You seem quite comfortable with evasion. If you're not here to honestly engage and explore, I would ask you to refrain from posting.

John99:

You have still failed to respond to post #27, above.



An example of Newton's third law of motion:

I exert a downwards force on my chair when I sit on it. The chair exerts an equal force upwards on me.


Not exactly.

That is a non-response that amounts to trolling.


His weight is pushing down but the seat is not pushing up and they are not equal either.

You will now answer the following questions:

1. If my seat does not push up on me as I sit in it, what stops me from falling through it to the floor?
2. Explain why the force of my chair pushing upwards on me is not equal to the force of me pushing down on the chair, with specific reference to Newton's Third Law of Motion.


Unless his chair has a spring. What kind of chair is this?

3. Explain exactly how a spring makes any difference.


That isnt what is happening. It is an incorrect application of the third law of motion.

4. Explain in detail the correct application of Newton's laws of motion to this example.

----

John99:

Being ignorant and uneducated, or just plain stupid, is no crime. But asserting that those who are educated and not stupid are wrong, without providing a shred of evidence for such claims, amounts to trolling, pure and simple.

The only possible aim I can see for you here is to provoke angry reactions from people who have an education in physics, and in particular those who understand the application of Newton's laws of motion.

You have 24 hours (or until whenever you next post, whichever is later) to respond to all of the questions in this post in full, OR, as an alternative, to publically post that you were mistaken and that you do not undertstand Newton's third law of motion.

Failing either of those actions, you will be temporarily banned from sciforums for trolling.

Have a nice day.

John99,

The clock is ticking.....

I read from wikipedia, the link shown by John99
http://en.wikipedia.org/wiki/Reaction_(physics)#Examples_of_common_misunderstan dings
about three times and I'm still not in clear yet.I learned it otherwise and I knew otherwise.
Please carefully read the link Reaction (http://en.wikipedia.org/wiki/Reaction_(physics)), from which I reproduce only a part.

Examples of common misunderstandings:

-Action and reaction are often confused with the issue of equilibrium. For example, consider the following statement:

"A book standing still on a table is at rest because its weight, a force pulling it downwards, is balanced by the equal and opposite reaction of the table, a force pushing it upwards."

This statement is misleading in that it suggests that the force exerted by the table on the book is the reaction associated with the book's weight. This is not the case, since the two forces are different in nature and are both applied to the book; one cannot be the reaction to the other, since they must apply to different bodies. In fact the force exerted by the table can be seen as the reaction to the contact force exerted by the book on the table, which in turn is equal to the book's weight.

Is the problem perhaps that John99 is confusing energy for force? Specifically, kinetic energy. Okay, I realise that they are not mutually exclusive concepts. I'm a beginner at this stuff myself but...
I couldn't help asking.



John99:


Explain exactly how a spring makes any difference.

He may be thinking of the stored energy in the spring. That energy would be capable of causing the person on the chair to be visibly pushed up.



If my seat does not push up on me as I sit in it, what stops me from falling through it to the floor?


Maybe your referring to the upward force of the chair makes him think of kinetic energy again. And the chair is not moving so he rejects your idea.


Well, John, is this the case do you think?