. Which of the following relationships between co-efficient of friction (μ)
between rock & roll and a (half of the angle of nip) of the particle to be
crushed is correct?
(A) μ > tan α
(B) μ ≥ tan α
(C) μ > tan 2α
(D) μ ≤ tan α

1 Answer

Answer :

(B) μ ≥ tan α

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