Science a GoGo's Home Page Forums General Discussion Physics Forum F=m0 not F=ma

F2=-F1

that will have to be my next topic.
clearly there's been some error.

ie...

1000 kg-m/s^2 vs .000000001 kg-m/s^2

I choose 1000 kg-m/s^2 as the victor in a head on confrontation.

why do I say that?
because if the two forces are equal and opposite
then nothing in mechanics would ever work.

in fact you could never walk down the street or get out of bed.
nothing could ever move.




what happened to the equal and opposite reaction in the above?
if the forces are always the same then the equal but opposite force that the ice is placing on the skaters skates would prevent their skates from moving.

so the skaters would not even move.

but Im always going against science anyway right?

ever wonder why?

maybe its because I find so many errors in science.



must be an error in the translation.
or it was taken out of context.
or newton was wrong!

We don't need anything to replace F=ma because it works just fine in its area of application, which is in a dynamic situation. In a static situation where there is no acceleration force still exists, it just doesn't meet the relationship, not the actual definition expressed by F=ma.

And that brings us back to my old Schaums Outline. The following is the discussion of the laws of motion.



Notice that in the second law the phrase "as a consequence is moving with velocity v" occurs. Now then if the force is acting on a particle which isn't moving, then F=ma no longer applies. We can develop a working method of measuring force by applying F=ma to a known mass with a known acceleration. Or we can develop a working method of measuring mass by applying a known force and measuring the acceleration. But the really basic definitions of force and mass are still the same ones that are in the last paragraph of the quote from Schaum's. Basically they are intuitive concepts that don't lend themselves to exact definition. Force is something that looks like a push or a pull. Mass is something that goes with objects. Actually I like to think of Mass as a quality of matter that resists a change in motion. And I like to think of force as something that tries to change the motion of matter.

Bill Gill

The forces will be equal and opposite. But according to F=mA which can be rearranged to say A = F/m then the acceleration of the 2 bodies will be much different. And your numbers are wrong. You are showing 2 different forces. But the 2 bodies will have the same force exerted on them, just in opposite directions. 2 bodies experiencing a force of the same magnitude but with different masses will experience different accelerations.

Bill Gill

but suppose
mass 1 = 1 kg
mass 2 = 2 kg

and they both have an acceleration of 1 m/s^2

magnitude of f1 = m1*1m/s^2 = 1 kg-m/s^2
magnitude of f2 = m2*1m/s^2 = 2 kg-m/s^2

f1 and f2 are not equal in magnitude!




force is the product of mass x acceleration

it doesn't say that the two bodies have equal mass
or equal velocity.
that's why I used two different forces.



that's impossible.
unless you plan ahead of time and adjust the accelerations
of the two masses or the mass of the two masses or both to achieve the same force.



I can agree to that.

Gentle readers: Once again we are subjected to Paul's refusal to actually think about what he is writing down so that he can see that it is completely wrong. Occasionally he makes a correct statement, then uses it in a totally inappropriate way to make a completely wrong point. He has been doing this as long as I have been following SAGG, so it shouldn't come as a surprise, but I am still amazed at his persistence in refusing to make any attempt to figure out how things really work.

As an example he is currently claiming that Newton's Laws of Motion are wrong. He completely ignores the fact that these laws have been used successfully by scientists and engineers for over 300 years, with no significant changes until Einstein developed the theory of Relativity. If they are wrong then the whole of the modern world is working under a serious delusion, since most of the developments up until the invention of Quantum Mechanics depended on the correct working of Newton's laws. Since the development of QM development of modern technology still uses Newtonian mechanics with a dose of QM on top to get into the modern digital age. So his claims are totally without foundation.

Bill Gill

your appeal for help never seems to attract any help
from the gentle readers.



I know how things really work , that's why I have issues
with this.

and I'm right.



I think that the laws have been misconstrued to fit in.



I dont see it that way.

first we have discrepancies with the symbols in physics.

then

we have discrepancies with the definitions in physics.

how hard is it to contemplate that sometime in the past
newtons words were misconstrued to fit into a slot.

F=ma is the issue , the a is the focus.

lets consider momentum.

P=mv

mass x velocity , requires motion.



you say that a force does not need acceleration.
so
do you also say that momentum also does not require velocity?

where will it end?

if you use a force to stretch a spring.

then clasp the extended spring to hold it in its expanded shape.

does the spring exert a force , or does the spring have tension? like potential energy Ep=mgh

you used a force to extend the spring.
and the spring will supply that force when you unclasp it.

but does the spring supply a force indefinitely while it is clasped in the extended shape.

I believe that is an example of why force requires motion.

lift a 10 lb brick and place it on top of a 10 ft ladder.

it now has potential energy. Ep=mgh

it can supply a 10 lbf for a distance of 10 feet = 100 ft-lbf.
but you had to put that much energy into the brick to lift it.
and the brick must move in order for you to use the potential energy you stored by elevating the brick.

does the brick exert energy sitting on top of the ladder?
No, it has potential energy but it exerts no energy.
those are reality situations.

they all require motion.

F=ma requires motion acceleration is the motion
P=mv requires motion velocity is the motion

there is no force without motion.

force requires motion

But Paul, I wasn't looking for help. I was just trying to let other people know to ignore your meaningless posts.

Bill Gill

yes, I will also ignore my meaningless post.

your so right , mr bill

In fact I have never found someone as smart and such a genius as
you are.

how do you do it?
how could anyone become as intelligent as you have become.

I think that you are approaching the level of intelligence
that einstein approached and books should be written about your
world renowned genius.

I do agree that posting on sagg is meaningless.

but its only meaningless because you and the other posers
here on sagg are so smart , so magical , so inventive with physics.

even newton himself would feel as if he were standing in your shadow.

all hail mr bill and his poser group on sagg


strike a pose

I've had about enough of this tripe. Either get on topic and act like an adult, or go find somewhere else to post your video clips. If you can't even go one post without insulting someone you need to grow up and act like an adult. Exchanging insults and linking to music videos are not an adult mode. Respect those who hold views opposing your own, if you want to be respected for your views.

R2

its really odd that you jump in and correct me when I
am "insulting someone".

where are you when I am the one being insulted?

poser

Don't piss off the moderator.

Tut, tut!

Can I be a Mod?

I don’t have enough hair for a Hitler haircut, but I might manage the moustache.

Cancel that, Donette says she will leave me if I grow one of those.

oh , so all the posers on sagg can piss me me off all they want
and the moderator never steps in and pisses them off.

but if I piss someone off then the moderator is right there telling
me that I shouldn't piss people off.

piss off

anyone know the meaning of that?

Paul,

You are the one doing most of the instigating. You deliberately provoke people by insulting them and then whine when you get called names in retaliation. What goes around comes around. If you don't want the discussion to degenerate into name calling and mud slinging, don't lead the way there. Grow up and learn to respect your fellow posters. If you will respect them, and not start with the name-calling, you will find you'll get better results.

I think you need to start from the beginning of the post R2.

I'm not sure how much more you could grow up , but recognizing
your own failures was suppose to be a part of it , if you fail
to moderate , then things can get out of hand.

you really need to learn physics in order to moderate in a physics
forum.

if there are 5 members ganging up on 1 member claiming that
2+2=0 then you would see the ganging up.

but if you don't know physics and there are 5 members ganging up on 1 member saying that F=ma does not mean force equals mass times acceleration then you wouldn't recognize it because you would only have reasoned it the way people who don't know physics reason it.

read before you plead.