Experiment with heated stretched springs.

[Low-Q]

I have a spring made of steel. The spring is stretched out, and kept in that position. There is now potential energy in the stretched spring due to tension. If I heat the spring up to 700 degrees celcius, the tension in the stretched spring disappear, and when the springs cools down it is permanently stretched, and I must apply energy to compress it into initial shape.

Where did the potential energy in the stretched spring go? Did I destroy energy or what happend?

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[gsal]

do you know where the springness of a spring comes from, in the first place?

it has to do with the fact that it is a solid and the fixed position of its molecules.

when you stretch the spring and heat it up to a certain temperature...you are basically 'melting' it a bit and putting heat into the system to allow molecules to re-position (re-distant) themselves, release stresses and settle on a new position of minimum potential energy.

you may want to read up on metallurgical processes like annealing.

and yes, 700 degrees is just about the annealing temperature for steel.

 

[Low-Q]

do you know where the springness of a spring comes from, in the first place?

it has to do with the fact that it is a solid and the fixed position of its molecules.

when you stretch the spring and heat it up to a certain temperature...you are basically 'melting' it a bit and putting heat into the system to allow molecules to re-position (re-distant) themselves, release stresses and settle on a new position of minimum potential energy.

you may want to read up on metallurgical processes like annealing.

and yes, 700 degrees is just about the annealing temperature for steel.

Does this mean that the metal will release its tension as heat? Say I use 1J to stretch the spring, then the spring release 1J of heat when I heat it up?

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[sophiecentaur]

Yep.

 

[sardar]

, thank you for sharing your experiment with heated stretched springs. It is an interesting and important area of study in the field of materials science. In response to your question, the potential energy in the stretched spring did not disappear or get destroyed. Instead, it was converted into thermal energy when the spring was heated to 700 degrees Celsius. This thermal energy caused the atoms in the steel to vibrate more rapidly, resulting in the spring losing its tension and becoming permanently stretched.

When the spring cools down, the thermal energy is released, but the atoms have already shifted into a new equilibrium state, causing the spring to maintain its stretched shape. In order to restore the spring to its initial shape, energy must be applied to overcome the new equilibrium and compress the atoms back into their original positions.

This experiment demonstrates the principle of energy conservation, where energy is neither created nor destroyed, but can be converted from one form to another. In this case, the potential energy in the stretched spring was converted into thermal energy, but the total amount of energy remains the same. This concept is crucial in understanding the behavior of materials and how energy is transferred and transformed within them. Thank you for sharing your findings and contributing to the advancement of scientific knowledge.