An ideal gas is taken through a cyclic thermodynamical process through four steps Q1 = 5960J, Q2 = –5585J, Q3 = –2980J and Q4 = 3645J, respectively. The corresponding works involved are W1=2200J,W2=−825J,W3=−1100J and W4 respectively. The value of W4 is:
765J
In a cyclic process ΔU=0
1st law of thermodynamics
Q=ΔU+WQ1+Q2+Q3+Q4=W1+W2+W3+W45960−5585−2980+3645=2200−825−1100+W4W4=1040−275W4=765J