81. If the barometric pressure at a place is 'h' mm of mercury, convert into SI units.
82. Four psychrometric processes P, Q, R and S are shown in the psychrometric chart below. These processes respectively represent
83. Effective temperature is estimated from
84. Bypass valve in a compressed oxygen type self-contained breathing apparatus is meant to
85. In the Coward flammability diagram, the respective percentages of methane and oxygen at the nose limit are
86. The total pressure and the static pressure measured at a point in a ventilation duct are 20 mm and 10 mm of water gauge respectively. If density of air is 1.2 kg/m3, the velocity of the air in m/s is
87. 20 m3/s of air flow through a long wall panel having 1000 tpd of production. Between the intake and return of the panel, the firedamp increases from 0 to 0.2%. The rate of firedamp emission is
88. A fan running at 200 rpm develops a pressure of 50 mm water gauge; the fan speed is increased to 300 rpm. the water gauge developed will be
89. If the $$\frac{{CO}}{{{O_2}}}$$ deficiency ratio in a mine is 2%, it indicates
90. A main fan of a mine circulates 40 m3/s of air at a pressure of 500 Pa. the mine has two splits of equal resistance. The trunk airways have a total resistance of 0.2 Ns2/m8. When a booster fan is installed in one split, the flow of air in the other splits stops. Assuming that the pressure remains unchanged, the new air quantity flowing through the mine in m3/s is
Read More Section(Mine Ventilation)
Each Section contains maximum 100 MCQs question on Mine Ventilation. To get more questions visit other sections.