Fifteen joules of heat are added to a cylinder with a piston. The system uses 7 joules of energy to raise the piston upward. By
2 answers:
The first law of thermodynamics states that:
where
is the variation of internal energy of the system
Q is the heat absorbed by the system
L is the work done by the system on the surrounding.
In this problem, the system absorbs 15 J of heat, so Q=+15 J (with positive sign, since it is heat absorbed by the system) while the work done by the system is L=+7 J (with positive sign, since it is work done by the system), so the variation of internal energy is
where
Q is the heat absorbed by the system
L is the work done by the system on the surrounding.
In this problem, the system absorbs 15 J of heat, so Q=+15 J (with positive sign, since it is heat absorbed by the system) while the work done by the system is L=+7 J (with positive sign, since it is work done by the system), so the variation of internal energy is
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we can write this in terms of horizontal ()and vertical component (
).
Horizontal component:
Vertical component:
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Answer:
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Explanation:
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= Density change due to motion
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c = Speed of light =
Relativistic density is given by
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