One gm mole of an ideal gas at S.T.P is subjected to a reversible adiabatic expansion to double its volume. Find the change in internal energy in the process. Given gamma = 1. 4 [E.Q.]

One gm mole of an ideal gas at S.T.P is subjected to a reversible adia

1.	One gm mole of an ideal gas at S.T.P is subjected to a reversible adiabatic expansion to double its volume. Find the change in internal energy in the process. Given gamma = 1. 4 [E.Q.]
Answer» Solution :`T_(1) = 273 K, T _(2) = GAMMA = 1.4` Final volume `V_(2) = 2 xx `Initial volume `V_(1)` `(V _(2))/( V _(1)) = 2` `T _(1) V _(1) ^( gamma -1) = T_(2) V _(2) ^( gamma -1)` `T _(2) = ((V _(1))/( V _(2)) ) ^( gamma -1) xx T_(1) = ((1)/(2)) ^( 1. 4 -1 ) xx 273` `= 20 7 K` Changle in interanl energy `dU = (R )/(( gamma -1)) = (T_(1) -T_(2))` `= (8. 31)/( ( 1. 4 -1)) ( 273 - 207)` `= 1. 37 xx 10 ^(3) J`