Is mass a measurement of energy?

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SUMMARY

The discussion centers on the relationship between mass and energy, specifically whether physical objects can be considered as clumps of energy measured as mass. Participants clarify that energy is a property of particles and fields, not a physical substance. The equation E^2 = m^2 c^4 + p^2 c^2 is highlighted as fundamental, illustrating that while mass and energy are related, they are not interchangeable, especially when considering objects in motion. The conversation also addresses misconceptions about light, emphasizing that while light possesses energy, it does not have mass.

PREREQUISITES
  • Understanding of mass-energy equivalence
  • Familiarity with Newton's laws of motion
  • Knowledge of momentum and its relation to energy
  • Basic grasp of electromagnetic theory, particularly the Poynting vector
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  • Research the implications of E^2 = m^2 c^4 + p^2 c^2 in relativistic physics
  • Study the concept of massless particles and their properties
  • Explore the relationship between energy and momentum in different physical contexts
  • Investigate electromagnetic fields and their effects on physical objects
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Physicists, students of physics, and anyone interested in the fundamental principles of energy and mass, particularly in the context of relativity and particle physics.

Cody Richeson
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That's pretty much it. Are physical objects essentially clumps of energy, and that energy is measured as mass? And do objects become more massive as they receive more energy through push?
 
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Energy is not a substance, it is a property of particles and fields.
 
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When you say it is a "property of particles and fields," what exactly is being literally described? Is energy one of those fundamental abstracts that lacks an underlying framework of smaller constituents? Is it one of those concepts that is without physicality, like temperature and charge?
 
Cody Richeson said:
That's pretty much it. Are physical objects essentially clumps of energy, and that energy is measured as mass? And do objects become more massive as they receive more energy through push?

Yes, it seems to be so. Energy is physical object that is not a clump, but more like fluid. While a physical object is energy in clumped state.Like, for example:

A power plant, burning coal lumps, is located at north pole, a city is at equator, power lines connect the plant and the city. When power is transmitted, the power lines droop to the west, because of the Coriolis force that is affecting the stuff flowing from the pole to the equator.
 
jartsa said:
Energy is physical object that is not a clump, but more like fluid.
No ot isn’t. It is a property of matter and radiation and that is useful in describing those. It is not even a Lorentz invariant property so it is meaningless to state ”I have X energy”.
 
Orodruin said:
No ot isn’t. It is a property of matter and radiation and that is useful in describing those. It is not even a Lorentz invariant property so it is meaningless to state ”I have X energy”.

How do we correctly describe 1000 J of energy going into a battery?

Maybe: 'Battery's energy property becomes larger'. Or 'battery becomes more energetic'.

As the battery becomes more massive in that process, I like to think the energy has mass. When energy has mass it approximately obeys Newtons law's. So it obeys same laws as matter.And how do we correctly understand the my power line example in post #4? Particularly in case of direct current?

Like this maybe:

There is an electric field and there is a Poynting-vector, and nothing is moving, when the vector points one way the lines hang one way, when the vector point the opposite way the lines droop the opposite way, and this has nothing to do with Coriolis-force?
 
Last edited:
Cody Richeson said:
That's pretty much it. Are physical objects essentially clumps of energy, and that energy is measured as mass? And do objects become more massive as they receive more energy through push?
Not exactly. Objects gain momentum and energy, not mass, when they are pushed.
The main equation relating them is
##E^2 = m^2 c^4 + p^2 c^2##
where E is energy, m is mass, p is momentum, and c is a unit conversion factor relating distance and time.
Often this is simplified to ##E = mc^2## for a case of an object at rest. But if you push an object, it is no longer at rest. Pushing is another way of saying, adding momentum to. This increases p, and by the equation must also increase E when m is constant.

Sometimes you will see statements saying mass and energy are equivalent, but as we have seen, this only makes sense for objects at rest.
 
Cody Richeson said:
That's pretty much it. Are physical objects essentially clumps of energy, and that energy is measured as mass? And do objects become more massive as they receive more energy through push?

Light has energy, but it has no mass. So already your premise has been shown to be false.

Zz.
 
correct me if I am wrong but If you combine the following equations:
photon energy: E = ħc/λ
mass–energy equivalence: E = mc2

you can quantify the mass of light as: m = ħ/λc
 
  • #10
unix101os said:
correct me if I am wrong

You're wrong.
 
  • #11
Vanadium 50 said:
You're wrong.
would you care to correct me?
 
  • #12
unix101os said:
would you care to correct me?
Because the correct formula (already given in post #7) is ##E^2 = m^2 c^4 + p^2 c^2##
 
  • #13
unix101os said:
would you care to correct me?
See post #7 for the correct formulation.
 

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