What are alternative definitions of energy in physics?

[Avgiu]

I have heard one definition of energy meaning a degree of inertial resistance... can anyone give me a different working condition for the word

 

[moose]

Degree of inertial resistance sounds more like mass to me... *shrug*

 

[z-component]

In physics, energy is the capability of something to do work. And yes, a "degree of inertial resistance" is mass.

 

[Ki Man]

yea degree of inertial resistance does sound like mass. but mass is energy according to E=MC^2 so i guess its right in a way. my pinky is energy along with my textbook and keyboard

 

[blt93932]

Matter is not energy, matter can become energy and vice vesa.

 

[Danger]

I'm not quite in agreement with that, but it might be just a matter of me using the wrong terminology. Given the wave functions involved, I always consider matter to be energy in a bound state, roughly analogous to ice being water in a bound state.

 

[PatPwnt]

Matter IS... another form of energy or vice versa

 

[HallsofIvy]

"Energy" is a bookkeeping device (how many words do you know with three double letters in a row?). People noticed long ago that kinetic energy is conserved in simple collisions so developed "conservation of energy". Of course, if the collision is not "elastic" that doesn't work so they added "heat" as a type of energy to "explain" that (and keep "conservation of energy" true). When relativity made it clear that mass could be converted to energy (and vice-versa) mass itself was declared a kind of energy just to make "conservation of energy" still work!

 

[pmb_phy]

I have heard one definition of energy meaning a degree of inertial resistance... can anyone give me a different working condition for the word

The term Inertial resistance has never been defined in physics. Let me offer this;

inertia is defined as the amount by which a body resists changes in momentum. So what would you call something which resist a change in momentum? I'd call that "force" in that F = dp/dt.

The definition of energy is given here

http://www.geocities.com/physics_world/mech/what_is_energy.htm

Pete

 

[Mk]

This question is constantly posted at physicsforums, here is one
https://www.physicsforums.com/archive/t-85718_What_is_energy.html