Miscellaneous In Mining - Study Mode

Show All Answers

[#176] Dustyness of a place may be considered at dust content less than . . . . . . . . the air is not dusty as per Russian text book.

(A) 1 mg/m 3

(B) 5 mg/m 3

(C) 10 mg/m 3

(D) 100 mg/m 3

Correct Answer

(A) 1 mg/m 3

[#177] The flame safety lamp is safe as long as it is not allowed to get unduly . . . . . . . .

(A) Wet

(B) Cool

(C) Fire

(D) Hot

Correct Answer

(D) Hot

[#178] If the mines are said to be extremly dusty, if the dust content.

(A) 1 mg/m 3

(B) 100 mg/m 3

(C) 20 mg/m 3

(D) None

Correct Answer

(B) 100 mg/m 3

[#179] The interval of bore holes should not be more than . . . . . . . . while working near water lodged workings.

(A) 3 m

(B) 5 m

(C) 7 m

(D) 10 m

Correct Answer

(B) 5 m

[#180] Calculate the w.g of a fan has to develop for ventilation tunnel under following conditions. The surface area is 2160 m 3

Area = 7.2 m 2 . Coeff. of resistance 0.00161 mm of wg/m 3 . Quantity of air passing is 6 m 3 /sec.

(A) 0.235 mm wg

(B) 0.335 mm wg

(C) 0.435 mm wg

(D) None

Correct Answer

(B) 0.335 mm wg