What is energy, in its simple form?

[ChileanOne]

maybe the "non existant" centrifugal force is the way that Milkovic exploits to induce a localized time variation change in the gravity field affecting the pendulum.

Hmmm.

[ResinRat2]

As you ponder energy, force, and work. Consider this example.

The performance of isometric exercise involves the pressing of the body against an immobile object with full strength achievable in most cases.

Since Work =  Force X Distance then no work was performed since distance is equal to zero. Yet you have reached the state of high heart and respiration rate. You are also sweating because you produced heat.

Since Force = Mass X Acceleration then no force was applied since acceleration was zero. Yet you can reach the point of total exhaustion by using all your might with a Force of zero.

Energy was depleted but in this case it was chemical, brought about by the Force of your Will. So does a will have energy? If will can be an energy, then how do you define energy?

My point is, you need to define what energy you are trying to explain. There is thermal, chemical, electrical, nuclear, etc.

I think your question is too vague. It needs clear paramaters for a definition.

[ChileanOne]

ResinRat:

Thanks for following. I think the analogy of pushing a wall is flawed because there is movement at the level of the miofibrilles on the pusher's muscle, so the E=Fxd remains true, only non obvious.

I'd say that a better idea for this would be the nail in the wall, where one can hang a mass. Then, still there is not energy spent after you store the potential by lifting the mass against the gravity field. The constant push down of gravity is being cancelled by the strong nuclear forces that hold the nail in the wall and keep the mass together. We still have forces acting against each other and cancelling out, but not movement. If gravity and/or nuclear forces would vary, the mass would move trough times, as a result of a change in potential energy trough time, thus one could see energy being created and/or destroyed. The key is to find the ways in which the force fields vary relative to each other and with respect to time, there is the source of infinity energy, and that's what Steorn seems to have found.

regards.

[Kent767]

I see a little bit of logical fallacy going on in this thread i'll try to clear it up.


Work is always force x distance (in terms of electricity its still equivalent, for example
1 watt = 1 joule/sec   or... 1 watt is enough electricity to move a 1 kilogram weight 1 meter against gravity in 1 second.

regarding work without motion and forces without motion.

a force is defined  F = M*A

you can have a force without motion, the tension on a cable on a suspension bridge is a force, it can be measured in Newtons, or the ability to lift 1 kilogram against gravity. 

Work on the other hand, cannot be done without motion.
you can have a magnet holding something to the fridge for an eternity but there is no work being done, there is a force, but no distance.

conversely, an asteroid travelling through empty space over some window of time is not performing work, because there is no force acting on the asteroid (distance without force)

slowing down this asteroid would involve work because you're changing the momentum of the asteroid.

[ResinRat2]

Sorry, what I should have said was the sum of the forces was zero. The forces being my force(pushing) against the wall and the wall resisting my push. Total of the forces equal to ZERO.

Sorry for the mistake.