New View Topic 1 Work-Energy

[absolute1]

I invite all of you to discuss about this science topic. We'll keep this to high school level . The concept will be straight forward and let's keep it as straight as possible. If you feel like this interfear with your basic understanding and have negative effect on school. I advice you not to join the discussion. If you have a disagreement, please say I disagree and give reason. There's no need to get the seriousness to level 3. What's level 3? Just some point. lol The topic I'm currently thinking of is Work-Energy theorem. I think this is the most important topic in science and needs more attention and effort on. Let's kick off:

 

Energy has many forms. Work is one form of energy. I have two extra clues. One is pointed out by a scientist (godless his soul, I forgot his name) that Work is a higher order of energy. What he meant was that work can transform 100% to heat, but heat cannot transform 100% to work. Well, the second clue already said, heat engine can never be 100% efficient. Let's take a case on static force. The great question would be "Can static force do work?" . No? That's right, static force can not do work. Work is force times displacement in the same direction. No displacement, no work. The first great question lead to the second great question. "Can static force generate energy?" I have to stop on this one. Let's think about the scenarios. Rock sitting on other rock. A small electric motor pushing on a house, magnet cling against gravity, statue spead arms, you holding a book. Do they generate energy? I know some do. Magnet will fall after a certain period of time. Statue arm will crack and fall. Your hamburger and 2 chicken wings in your tummy used up. Motor will burn. However, nothing will budge. So in a way, yes. Maybe the work we put in is the lower end portion of the heat engine, meaning the inefficient portion. Let's assume you're lifting up a car weight 1 ton by yourself. Being so strong, you lift it with half a ton force. Nope, no cigar. Let's use leverage. Hey it works. So the force I spend is not useless after all. I can sweat and do no work, or I can sweat and do some work. We can conclude that static force generate energy. How much? There's no formula for it? Force times distance? what distance? 100yard? 10 km? Yep, dunno, but one thing for sure is that force is proportional to energy generate. So let's ask time for help. Time will keep us tract of our energy. Whoops, we stepped energy from static force to power. So.. with a certain force, a certain power generate. Let's take a break... If you are not disagreeing with this, you might ask well wanna pack your stuff. We're going to see Alpha Centauri.

[Klaynos]

Can you define what you mean by "static force"?

 

A ton is not a measure of force, unless of course you are refering to the "short ton" when you should probably state as such.

 

Again what do you mean by static force? If the force is moving a lever how can it be static?

 

In this case it would be the force due to gravity * height * the mass of the thing moved. Which I don't know in the units you are using.

 

You're thread doesn't seem to really have a point to it and the conclusion is just drawn from thin air it appears.

[absolute1]

Hi,

 

A ton is a measurement of weight. Some country use it, some use kiloNewton, some use kips. Anyay, it's not mass, it's weight. Static force is force pushing against something, but they do not move that object. You're sitting on a chair, you're exerting a static force on the chair.

 

You're describe the force of mass*gravity*height is the force needed to move the object. My point was that if you put all your might to lift a car, it doesn't matter if you lift it or not, you'll exhaust energy. The same amount of energy independant of the car lifted or not.

[ajb]

You can think of energy as the ability to do work. Where work is defined as [math]W=F\cdot d[/math], where [math]F[/math] is the force and [math]d[/math] the displacement. You can also view this as a change in energy.

 

I think your statement about "higher energy" is nothing but entropy. Kind of the measure of a system not to be able to do work. Heat is really the flow of energy rather than the energy. Anyway, I think what you have said is the second law of thermodynamics.

[absolute1]

ajb,

 

So I can view energy as the ability to do work. What you saying is when I am unable to lift a car up, i'm exhausting my ability. I can view work as a change in energy. So by unable to lift a car, i am unable to do work, but I have a change in energy?

 

Forget it for a bit, let's help me do this. This doesn't add up for some reason and it makes no freaking sense at all.

 

Suppose I push an object with for F in space with mass m for period of time t. The impuse will then be Ft=mv1. The energy the mass gain is 1/2 mv^2.

 

Suppose I push an object with force F in space with mass 2m for the same period of time t. The impuse will then be Ft=2mv2. V2 is now 1/2v1. The energy the mass gain is 1/2*2m*(v1/2)^2 = 1/4mv1^2 . What in the dead twightlight zone is that? Can someone tell me what am i missing in the energy momentum concept? God I surely hope this is not a special case in energy momentum principle.

 

I'm sorry but I just lost all interest bringing up topics for discussion in here. I'll be unactive until this resolve. I'm stuck on a simple energy momentum problem, unable to give myself a simple answer. Obviously either momentum or energy is conserve and both cannot be at the same time. Maybe this is the answer I've been seeking. That scientist did have a point in his example after all. This is too crazy to comprehend, thus exciting. I must investigate this matter in details. Keep in touch, I know you will miss me.

 

Take care all

[Phi for All]

I'm sorry but I just lost all interest bringing up topics for discussion in here.

No need to be sorry. I'm giddy with glee, myself.

 

Thread closed.