We know that the high pressure liquid refrigerant (comming from condenser) passes through the expansion valve and lowers the temperature (due to decrease in pressure).
My Question: From the formula pV = nRT: (p1V1) / T1 = (p2V2) / T2 [ n & R are constant] So, if the pressure (p2) decreases, either volume (V2) should increase or temperature (T2) decrease. Then, why only the temperature (T2) decreases. It can rather be isothermal process in which temperature remains constant (T1) and volume (V2) may increase. Moreover, this process of expansion of gas is very fast and we know that transfer of heat will not get sufficient time. So temperature should remain conatant and volume should increase. But actually, it does not happen. Why?