Question

Critical Speed (Nc) of a ball mill is given by(where R₁ and R₂ are radii of ball mill and the ball respectively).

a.

A

b.

B

c.

C

d.

D

Answer: (b).B

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Q. Critical Speed (Nc) of a ball mill is given by(where R₁ and R₂ are radii of ball mill and the ball respectively).

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