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The quantity of energy available in the universe is a constant.
Heat (q) is the transfer of energy due to difference in temperature.
Temperature is a measure of how hot or cold an object is.
The direction of heat transfer is shown by the sign of q.
For any process, heat transfer is complete and
q(surroundings) = –q(system).
Roll your mouse over the image to see that the sign of ΔT for the surroundings/system is the same as the sign of the corresponding q.
Thus a change in the energy of a system results in an equal and opposite change in the energy of its surroundings. Energy may be transferred between the system and surroundings as heat.
Heat (q) is the transfer of energy due to difference in temperature.
Temperature is a measure of how hot or cold an object is.
As you know, when a hot and cold object are in contact, heat is transferred from the hot object to the cold object until they have the same temperature.
Roll your mouse over the image.
Roll your mouse over the image.
The direction of heat transfer is shown by the sign of q.
If, for a process, q(surroundings) is
positive
heat has been transferred to the surroundings.
negative,
heat has been transferred from the surroundings.
positive
heat has been transferred to the surroundings.
negative,
heat has been transferred from the surroundings.
For any process, heat transfer is complete and
q(surroundings) = –q(system).
Roll your mouse over the image to see that the sign of ΔT for the surroundings/system is the same as the sign of the corresponding q.