00:00Numerical number 6 of unit 16 first law of thermodynamics is a gas expands from 0.03
00:15meter cube to 0.06 meter cube against a constant pressure of 100 kilopascal. Calculate the work
00:24done in both a reversible and an irreversible process and compare the results. So,
00:32first of all, we will create data, initial volume V1 is obtained as 0.03 meter cube and final volume V2
00:55is obtained as 0.06 meter cube and pressure is obtained as here is 100 kilopascal.
01:10So, 10 kilopascal is equal to 1000 pascal. So, 10 cube is equal to 1000 pascal. So,
01:2810 into 10 raised power 3 pascal because 1 kilopascal is equal to 1000 pascal. So,
01:3810 cube is equal to 1000. So, when we multiply 10 with 1000, then pressure will be 10,000 pascal.
01:51So, we have to find work done in both conditions means for irreversible process and work done for
02:10reversible process. So, for solution or calculation,
02:17first, first we will find work done for irreversible process which is the work done for irreversible
02:27process is calculated by using formula W is equal to P delta V. So, we can also write this as
02:37delta V as delta V is equal to V2 minus V1 means final volume minus initial volume. So, work done
02:52for irreversible process will be as pressure is 10,000 pascal into V2. V2 is 0.06 cubic meter
03:08and V1 is minus V1 is 0.03 meter cube. So, work done for irreversible process will be
03:1910,000 into 0.06 minus 0.03 so it will be 0.03. So, work done for irreversible process will be
03:3110,000 into 0.03 it will be 300 Joules. So, this is answer for irreversible process.
03:47Now, we will calculate work done for reversible process.
03:59Work done in irreversible process will be equal to the twice of the work done
04:06by irreversible process. So, net work done by irreversible process will be equal to the
04:11work done by irreversible process. So, net work done by irreversible process
04:29So, net work done by irreversible process will be equal to 2 into 300. So, it will be 600 Joules.
04:46So, this is our second answer.
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