51) Belt conveyor can be used to transport coal at an inclination up to

52) The correct mixture strength (by weight) for a petrol engine is about

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