Home/Volume-2/Distribution of Air and Its Control-2 Volume-2 Distribution of Air and Its Control-2 Admin03/08/20242 31 Less than a minute Report a question What's wrong with this question? You cannot submit an empty report. Please add some details. 0% Distribution of Air and Its Control Distribution of Air and Its Control-2 1 / 25 1. When the air and mineral flow in the same direction the ventilation is called? Ascential ventilation Descential ventilation Homotropal Antitropal 2 / 25 2. The quantity of air to be circulated by an auxiliary fan depends upon? Length of the heading Number of persons in the drift Size of the drift Rate of emission in the roadway 3 / 25 3. In smoke generator for measuring air velocity the time taken by the smoke to travel....m is recorded? 4 - 6 m 6 - 8 m 8 - 10 m 10 - 12 m 4 / 25 4. In refrigerant circulation system the refrigerant used is? Ammonia Calcium chloride Freon-12 Carbon dioxide 5 / 25 5. The quantity of the air per minute should be..... per sq.m of working area? 2.5 cu.m 6 cu.m 7 cu.m 8 cu.m 6 / 25 6. Good and harmless refrigerant in the following refrigerants is? Carbon dioxide Methyl chloride Freon -12 Ammonia gas 7 / 25 7. Splits reduce the doors on haulage roads but? Increase pressure Decrease quantity Increase Number of air crossings none 8 / 25 8. If the booster is placed inbye of the neutral line? Leakage is maximum Zone of recirculation takes place Fan will damage none 9 / 25 9. Anemometers are used to measure air velocities between? 60 - 1000 m/min 0 - 10 m/min 10 -50 m/min 50 - 60 m/min 10 / 25 10. On reversal of air current by axial flow fan the quantity of air reduces to..? 20% 30% 40% 60% 11 / 25 11. The quantity of air drawn by an auxiliary fan from the air way should not exceed? equal to quantity 1/3 of quantity 3/4 of quantity 1/1.5 of quantity 12 / 25 12. The increase in the quantity of air due to expansion in the upcast shaft can be roughly taken as? 1 % for every 100 m 5 % for every 100 m 1 % for every 15 m 1 % for every 50 m 13 / 25 13. Profilometer is used for measuring? Air velocity Cross section of irregular shape Pressure of the air % of CH4 14 / 25 14. For obtaining good results measurement of quantity flowing through an airway on either side of velocity measuring point the roadway should be uniform in cross section for a length of? 2 m 5 m 10 m 15 m 15 / 25 15. Venturi tubes increased the air flow by? 10% 20% 30% 40% 16 / 25 16. The minimum distance between the fan and the corner of the drift to be ventilated should be? 3 m 4 m 5 m 6 m 17 / 25 17. Air lock doors are required to be arranged where pressure on the door is? more than 250 pa less than 250 pa more than 500 pa less than 500 pa 18 / 25 18. For measuring air velocities less than 1 m/sec........is used? Anemometer Velometer Smoke generator Pitot static tube 19 / 25 19. In anemometer the angle of yaw should be ? less than 30 deg less than 20 deg less than 15 deg less than 10 deg 20 / 25 20. Compressed air jets increased the air flow by ? 10% 20% 30% 40% 21 / 25 21. The effect of splitting the air in parallel is? Overall resistance of mine increases Overall resistance of mine decreases Pressure produced by fan increases Pressure produced by fan decreases 22 / 25 22. The vanes of the anemometers are ....deg to the direction of airflow? 20-Oct 20-30 30-40 40-50 23 / 25 23. The accuracy obtained in precise traversing is? more than 5 % 5% 3% 2% 24 / 25 24. The ventilating door should open against the intake air so that? Air leakage takes from intake to return The air pressure normally keeps the door closed Recirculation of foul air avoided Regulations are compiled with 25 / 25 25. The minimum reading with a velometer can be taken as ? 0.5 m/sec 0.05 m/sec 0.1 m/sec 0.01 m/sec Your score is The average score is 60% LinkedIn Facebook Twitter 0% Admin03/08/20242 31 Less than a minute
Good information sir
Thank you