Drilling And Blasting - Study Mode
[#256] Because of leakage the total quantity of air that reaches the working faces is only . . . . . . . . of that circulated by the main fan.
Correct Answer
(B) 25 - 50%
[#257] A higher NVP is produced in the workings in . . . . . . . .
Correct Answer
(B) Ascensional ventilation
[#258] The presence of angle of yaw for the animometer.
Correct Answer
(D) Estimation can be higher or lower depending an angle
[#259] The percentage of recovery in BG method is . . . . . . . .
Correct Answer
(A) 70-80%
[#260] Inflammability of coal dust increase almost . . . . . . . . proportional to the percentage of fire damp present in atmosphere.
Correct Answer
(B) directly