Can you change the state of matter by increasing the speed?

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Archmundada
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We all know that the state of matter can be changed by increasing temperature or by applying pressure. And, all of these, in some way lead to a change in the particles' speed. The speed of the particle decides the state of matter. So, if we were to throw an object at very high speeds, like 50% of the speed of light, the particles' speed will also increase, as they are a part of the solid. This means that, as we reach higher speeds, the state of matter should change, because the speed of particles has changed. We can also say that it will never be possible for a large solid to attain light-like speeds (Also, solids don't move, they vibrate. But, liquids and gases move. So, this question can probably change to liquid-gas condition, rather than a solid-liquid-gas condition). Can this happen in the real world? If not, please state why. And I am sorry if I made any silly mistakes, I don't know a lot about physics.
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  • #3
Ibix
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The speed of the particle decides the state of matter.
This is only half of the correct statement. In fact, it's the average speed of the particles relative to one another that affects the state of matter. Simply increasing the speed of a block of matter doesn't change that. For example we are doing 20 km/s round the Sun but we don't all boil.

This is, as trurle says, an example of the principle of relativity. If what you say were true then we could just carry a thermometer and use it to measure our speed relative to the absolute state of rest that your line of thinking implies. The world does not work that way.
 
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  • #4
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The speed of the particle decides the state of matter.
This is not correct. It is a fairly common misunderstanding of the concept of thermal energy.

Thermal energy is not specifically about microscopic kinetic energy, it is about energy stored in microscopic internal degrees of freedom. For an ideal monoatomic gas the only internal degree of freedom is the kinetic energy, but that is not true in general. Many substances also have vibrational and other internal modes that put energy in the microscopic equivalent of a spring instead of just KE.

The problem is that people are taught the connection between thermal energy and speed in the context of the ideal gas law. And even though it is clearly specified that the ideal gas law describes only ideal monoatomic gasses, people can’t help but generalize to other substances. Largely because the presentation of other thermal laws is not done from first principles.
 
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  • #5
DaveC426913
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So, if we were to throw an object at very high speeds, like 50% of the speed of light, the particles' speed will also increase, as they are a part of the solid. This means that, as we reach higher speeds, the state of matter should change, because the speed of particles has changed.
You need to be careful about your frame of reference.

If I were to throw a baseball at 50% of the speed of light, it would not change state (well, unless I did it within the atmosphere. Then it would change state rather spectacularly, but I digress...)

A state change will happen if the relative speed between molecules changes. The molecules have so much energy that it overwhelms the inter-molecular forces holding them together.

But a baseball moving at .5c doesn't have much velocity difference between its molecules - after all in its reference frame, it is stationary.
 
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