Energy Demystified

[steve_bank]

A derail from religion.

Energy is contextual.

There is subjective perception. I m depressed and out of energy. I feel energized.

There is the religious and the mystical. God is the energy of the universe. When I meditate I feel cosmic energy.

There is the fictional scifi use of energy as a plot device. Captain I detect a strange energy we have not encountered before.

There is the science definition of energy as the capacity to do work, work being force x distance or Newton Meters. Lift a 10lb weight 1 foot and you have done work. The chemical energy consumed is the work in Joules plus inefficiencies in the body, internal losses. It is why your body temperature goes up when exercising.

In the 19th century Joule showed with his paddle wheel experiment hat heat, work, and energy can be expressed in the same unit. Today it is the Joule.

Conservation of energy is simple. Consider coal powered plant

chemical energy in coal in joules goes to heat in Joules, heat goes to steam energy in Joules, steam energy goes to work turning a turbine generator, work in the generator goes to electric energy in Joules.

Energy has no independent reality, it goes through a series of transformations of form. The common thread is work. Moving electrons in a wire is work.With each transformation some energy is lost and can not be used to do work in the system. All of the chemical energy in the coal can not go to producing steam.



The test for something as energy is to be bale to do something with it.

If Zero Point Energy is real then work can be done.

 

[Swammerdami]

The test for something as energy is to be [able] to do something with it.

This phrasing is similar to a description of Gibbs Free Energy.

I hope one of our experts can present that concept more lucidly than Wiki/Google do.

 

[T.G.G. Moogly]

Would I be wrong to think of energy as some rendering or discussion of motion?

 

[steve_bank]

In the early days of radio there was debate over wether or not reflected energy back down a transmission line was real.

The question was answered using a directional coupler that shunted the return energy to a port with a resistor across it. A temperature rise was measured for the reistor indicating real power.

Energy has to have a form. A coal plant shows conservation, transformation from on form of energy to another. That is all there is to it.

If you want to ague something else go ahead. Any claim can be made, how do you test it?

In engineering a temperature rise is an ndicator of energy being consumed.

 

[skepticalbip]

Would I be wrong to think of energy as some rendering or discussion of motion?

Yup.

Though one form of energy is kinetic energy which is the energy of a mass in motion is defined as e=mv². But then the v (velocity) depends on what is being used as a reference by which the v is determined.

Chemical energy, nuclear energy, potential energy, etc. has nothing to do with motion, they are stored energy. Or even matter itself is stored energy as uncle Albert explained with his revelation that e=mc² which means that m=e/c². They are stored energy although things generally move when it is released.

 

[bilby]

Would I be wrong to think of energy as some rendering or discussion of motion?

Yup.

Though one form of energy is kinetic energy which is the energy of a mass in motion is defined as e=mv². But then the v (velocity) depends on what is being used as a reference by which the v is determined.

Chemical energy, nuclear energy, potential energy, etc. has nothing to do with motion, they are stored energy. Or even matter itself is stored energy as uncle Albert explained with his revelation that e=mc² which means that m=e/c². They are stored energy although things generally move when it is released.

The kinetic energy is approximately half mv², at velocities significantly lower than c.

Newton's formula for kinetic energy reflects this, and remains 98% accurate even at v=0.2c, so he's forgiven for not recognising that the supposed "constant" of 0.5 varies with velocity.

 

[T.G.G. Moogly]

Would I be wrong to think of energy as some rendering or discussion of motion?

Yup.

Though one form of energy is kinetic energy which is the energy of a mass in motion is defined as e=mv². But then the v (velocity) depends on what is being used as a reference by which the v is determined.

Chemical energy, nuclear energy, potential energy, etc. has nothing to do with motion, they are stored energy. Or even matter itself is stored energy as uncle Albert explained with his revelation that e=mc² which means that m=e/c². They are stored energy although things generally move when it is released.

But isn't "stored" energy still in motion? The motion has different bounds but all the motion is still there, just confined to less space.

Absolute zero doesn't happen because that would be the absence of all motion, or am I wrong again?

 

[skepticalbip]

Would I be wrong to think of energy as some rendering or discussion of motion?

Yup.

Though one form of energy is kinetic energy which is the energy of a mass in motion is defined as e=mv². But then the v (velocity) depends on what is being used as a reference by which the v is determined.

Chemical energy, nuclear energy, potential energy, etc. has nothing to do with motion, they are stored energy. Or even matter itself is stored energy as uncle Albert explained with his revelation that e=mc² which means that m=e/c². They are stored energy although things generally move when it is released.

The kinetic energy is approximately half mv², at velocities significantly lower than c.

Newton's formula for kinetic energy reflects this, and remains 98% accurate even at v=0.2c, so he's forgiven for not recognising that the supposed "constant" of 0.5 varies with velocity.

You are, of course right. A very careless omission on my part... a brain fart.

 

[skepticalbip]

Would I be wrong to think of energy as some rendering or discussion of motion?

Yup.

Though one form of energy is kinetic energy which is the energy of a mass in motion is defined as e=mv². But then the v (velocity) depends on what is being used as a reference by which the v is determined.

Chemical energy, nuclear energy, potential energy, etc. has nothing to do with motion, they are stored energy. Or even matter itself is stored energy as uncle Albert explained with his revelation that e=mc² which means that m=e/c². They are stored energy although things generally move when it is released.

But isn't "stored" energy still in motion? The motion has different bounds but all the motion is still there, just confined to less space.

Absolute zero doesn't happen because that would be the absence of all motion, or am I wrong again?

That is a different matter, thermal energy. The potential energy that bowling ball had because of being seven feet above the floor on the top shelf in the closet is gone after it rolls off the shelf, crushes your skull and comes to rest by your limp body. That particular potential energy ain't no more, it has done its work as a force, but the bowling ball is actually a bit warmer, so a bit more thermal energy. But as long as that bowling ball was sitting on that closet shelf, it had the potential energy... moral, don't store massive shit where it can fall on you.

You should also want be careful where and how you store things with plentiful stored chemical energy like your sticks of TNT and jars of nitroglycerine.

 

[steve_bank]

Good point on the bowling ball. When a batter hits a ball there will be a temperature rise however small.

Keep in mind emery is relative. Two cars at the same speed and direction can not do work with the kinetic energy relative to the ground. Energy is always proportional to a magnitude squared.

E= 1/2 mv^2
E = mc^2
E = 1/2 cv^2 capacitor

 

[untermensche]

Like all things in the universe humans have no idea what energy is. Only how it behaves in terms of constructed models. How it behaves in simple systems. Increase complexity and modeling becomes more difficult. The behavior within a cell can't be modeled.

 

[Shadowy Man]

Good point on the bowling ball. When a batter hits a ball there will be a temperature rise however small.

There’s also some sound.

 

[bilby]

Good point on the bowling ball. When a batter hits a ball there will be a temperature rise however small.

The temperature rise is quite measurable; In cricket, the question of whether or not the ball just touched the edge of the bat, or missed it completely, is critical to the game, and for big matches, a technology called 'hotspot'is used by the review umpire (and TV commentators) to help resolve that question. Hotspot uses in infrared camera to 'see' the residual heat on the bat where the ball struck it, and can detect even the slightest 'edge':



If the batsman strikes the ball firmly, the heat is even more obvious:

 

[steve_bank]

Good point on the bowling ball. When a batter hits a ball there will be a temperature rise however small.

There’s also some sound.

It is those pesky laws of thermodynamics....life would be a lot easier without them. Everything has to add up like a bank account.