Question #3bd67
1 Answer
Dec 16, 2017
Work is required to preform an expansion/compression.
Explanation:
In an expansion, the value of a system increases. The opposite of an expansion is a compression, in which the volume of a system decreases.
Simply put, work is required to alter the volume of a system.
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Work is done by the system on the environment to increase the volume of the system (an expansion)
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Work is done by the environment on the system to decrease the volume of the system (a compression)
This is clear from the equation for work:
#color(blue)(W=-int_i^fPdV)#
Where:
#P# is pressure (assumed to be constant)#dV# is the infinitesimal change in volume (we integrate over this)#i# is the initial state,#f# is the final state
In other words, the work done during a process in which the volume is not constant is the negative area under the pressure vs. volume curve.
We can then see that if there is no change in volume (an isobaric process),
