what is a force ?

[krista]

im not doing homework this time i just thinking about science since my mum is a teacher !! so dont have a go at me like some of you did last time cos im not doin homework !!!!!!!!!!!!!!!!!!

[boxtops]

So what is a force? here's the definition, this should explain it http://dictionary.reference.com/browse/force

[MarkRae]

Wow! You looked it up in a dictionary...??? I'd never have thought of that...

[krista]

thankyou boxtops sorry about me and erin i was in a bad mood my dad died !!!!!!

[boxtops]

Have you seen krista's previous questions, MR? - stop being so sarky.

[krista]

THANKS BOXTOPS YOU ARE REALLY STICKING UP FOR ME !!!

[krista]

WHAT IS AIR RESISTANCE?

[boxtops]

now you can start Googling, krista - this is a bit like the Frock Coat question.....

[NazNomad]

"Have you seen krista's previous questions, MR? - stop being so sarky."

I think the other questions provide every reason to be sarky, IMO.

When a correct answer is given, but contains extra information, it's always replied with a , "what is ...?"

As this thread seems to have turned out doing.




<waits for the inevitable, "what is a thread?" reply>

[krista]

BYE PEOPLE (LOVE YA IN FRIEND WAY !!!!!!!!!!!!!!!!)

[DTCwordfan]

From a phyics perspective it is a good question.

I quote a neat summary from Wilkipedia.


A force is any influence that causes a free body to undergo a change in speed, a change in direction, or a change in shape. Force can also be described by intuitive concepts such as a push or pull that can cause an object with mass to change its velocity (which includes to begin moving from a state of rest), i.e., to accelerate, or which can cause a flexible object to deform.

A force has both magnitude and direction, making it a vector quantity. Newton's second law, F=ma, can be formulated to state that an object with a constant mass will accelerate in proportion to the net force acting upon and in inverse proportion to its mass, an approximation which breaks down near the speed of light. Newton's original formulation is exact, and does not break down: this version states that the net force acting upon an object is equal to the rate at which its momentum changes.

[boxtops]

Yeah, I know naz, I was trying to give krista the benefit of the doubt. Hey ho.

[Old_Geezer]

One can describe it, say what it can do, list characteristics, but does that tell you what it is ? Sometimes I think I don't really know what anything is, I just accept things as being in some way. It has a label, I know how to use the word more or less.

[jake-the-peg]

trouble with google is that this is the sort of question that will give you a lot of answers and sorting the wheat from the chaff can be difficult.

I kind of like the wikipedia definition although it's not perfect as it only applys to a free body.

So for example gravity is a force acting on my computer but it is not moved or deformed because it is supported by the desk.

[DTCwordfan]

Jack - not quite true - with some of the comments here, my computer has experienced force from me and has moved and is now deformed from its experiences.

[jomifl]

Jake.. your computer stays where it is because the the force of gravity is opposed by an equal and opposite force. (provided by the desk)

[factor-fiction]

Krista's last thread ("What is a footman", or something like that) was removed. after reading her previous threads I'd need a lot of convincing before I'd spend any time helping her in future.

[boxtops]

me too, now, factor. ;-)

[jake-the-peg]

Strangely I am aware of that jomfl ;c)

I'm pointing out that because it's not a free body it falls outside of the Wikipedia definition.

[Rev. Green]

I still wonder about gravity.
The electromagnetic force, the weak force, and the strong force are real forces - or aspects of one hyper-force.
Coriollis force and centrifugal force are pseudo forces: they are still effective, but are effects of conservation of (angular) momentum.
But is gravity real or pseudo?