Drilling And Blasting - Study Mode

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[#686] The percentage of extraction of the depth of seam is 200 and width of gallery is 4.8 m.

(A) 33

(B) 20

(C) 25

(D) 40

Correct Answer

(C) 25

[#687] The fans of 760 mm size, backward bladed, what should be the maximum allowable gap between the impeller and the impeller inlet.

(A) 1 mm

(B) 3 mm

(C) 6 mm

(D) 8 mm

Correct Answer

(B) 3 mm

[#688] If the depth of workings of coal mine below 200 m said to be . . . . . . . .

(A) Shallow

(B) Moderate

(C) Deep

(D) Very deep

Correct Answer

(A) Shallow

[#689] The relation between size of coal and total methane gas content emitted at face.

(A) Directly proportional

(B) Inversely proportional

(C) In GP series

(D) In AP series

Correct Answer

(B) Inversely proportional

[#690] Water CO 2 extinguishers suitable only for quency of . . . . . . . .

(A) Class A fire

(B) Class B fire

(C) Class C fire

(D) Class D fire

Correct Answer

(A) Class A fire