49) A single stage impulse turbine with a diameter of 1.2 m runs at 3000 r.p.m. If the blade speed ratio is 0.42, then the inlet velocity of steam will be

50) In a De-Laval impulse turbine, the nozzle is kept very close to the blades.

51) The flow of steam is super-sonic

52) The pressure of steam at throat of a steam nozzle is called critical pressure.

53) For maximum efficiency of an impulse turbine, the steam should leave the blades at right angles to their motion.