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                                    Figure shows a cylindrical container containing oxyegn `(gamma = 1.4)` and closed by a 50 kg frictionless piston. The area of cross section is `100cm(2)` , atmospheric pressure is `100 kPa`+E2 and g is 10 m s^(-2)`. The cylinder is slowly heated for some time. Find the amount of heat supplied to gas if the piston moves out through a distsnce of 20 cm. . | 
                            
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Answer» `gamma =1.4`, Weight of piston (w) `= 50 kg`, Area of cross section of piston(A) `=100 cm^2` Atmospheric pressure `(P_0) = 100 kPa`, `g=10 m//s^2, x=20 cm`, `dW = Pdv= ((mg)/A+P_0).Adx` `= ((50xx10)/(100xx10^(-4)) + 10^(5))` `(100 xx 10 ^(-4) xx 20 xx 10^(-2))` `= (5xx10^(4) xx10^(5) ) xx 20 xx 10^(-4)` `= 1.5 xx 10^(5) xx 20 xx 10^(-4)` `=300 J`. Hence `nRdT = 300`ltbgt `dT= 300/nR` ltbgt So, `dQ=nCpdT=nc_p xx((300)/(nR))` `=(ngammaR300)/((gamma-1)nR` `= ((300xx1.4)/0.4)` `=1050J`  | 
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