Lost_Melon
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Question) Compare work done in extending mechanically with thermal energy gain to achieve the same extension.
For any extension, determine the value of (work down by mechanical extension ÷ thermal energy required for extension)

The only way I can think to link force and distance (which is work done) is using stress ÷ strain = youngs modulus. In terms of thermal energy I think specific heat capacity × mass × change in temp is the only way. I'm really confused as to how these would link.
Thank you very much in advance.
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RogerOxon
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(Original post by Lost_Melon)
Question) Compare work done in extending mechanically with thermal energy gain to achieve the same extension.
For any extension, determine the value of (work down by mechanical extension ÷ thermal energy required for extension)

The only way I can think to link force and distance (which is work done) is using stress ÷ strain = youngs modulus. In terms of thermal energy I think specific heat capacity × mass × change in temp is the only way. I'm really confused as to how these would link.
Thank you very much in advance.
You're going to need the coefficient of thermal expansion too. Think about how to get a measure with the same dimensions for each.
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Lost_Melon
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(Original post by RogerOxon)
You're going to need the coefficient of thermal expansion too. Think about how to get a measure with the same dimensions for each.
Ah I just realised the question relates to a specific material, and meant any extension of that material, not any extension of any material. I was just wondering, for work done the force will be the force used in stress, but what will the distance be (since work done = force × distance), the extension of the material or the total length?
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RogerOxon
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(Original post by Lost_Melon)
Ah I just realised the question relates to a specific material, and meant any extension of that material, not any extension of any material. I was just wondering, for work done the force will be the force used in stress, but what will the distance be (since work done = force × distance), the extension of the material or the total length?
For both thermal and mechanical extension, calculate the strain per Joule.

Take a cross sectional area A and an initial length l. You should be able to get to the units above.
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