53) At a certain pressure, the sensible heat of water is 800 kJ/kg, enthalpy of evaporation is 2000 kJ/kg. If the dryness fraction of the steam is 0?5, then the enthalpy of wet steam is

54) Which among these is a water tube boiler ?

55) In S.I. units, one tonne of refrigeration is equivalent to

56) The ratio of moment of inertia of a circular body about x-axis to that about y-axis is

57) A mass of 5 kg is attached to the middle of a rope, which is being pulled from both ends in the opposite directions taking g = 10 m/square seconds. The minimum pull required to completely straighten the rope will be