Two rods one made of copper and other made of steel of same length and same cross sectional area are joined together. The thermal conductivity of copper and steel are 385 J s^$$-$$1 K^$$-$$1 m^$$-$$1 and 50 J s^$$-$$1 K^$$-$$1 m^$$-$$1 respectively. The free ends of copper and steel are held at 100$$^\circ$$C and 0$$^\circ$$C respectively. The temperature at the junction is, nearly :

Three vessels of equal capacity have gases at the same temperature and pressure. The first vessel contains helium (monoatomic), the second contains fluorine (diatomic) and the third contains sulfur hexafluoride (polyatomic). The correct statement, among the following is :

An ideal gas undergoes four different processes from the same initial state as shown in the figure below. Those processes are adiabatic, isothermal, isobaric and isochoric. The curve which represents the adiabatic process among 1, 2, 3 and 4 is

The volume occupied by the molecules contained in 4.5 kg water at STP, if the intermolecular forces vanish away is