# What is the critical rotation speed in revolutions per second, for a ball mill of 1.2 m diameter charged with 70 mm dia balls ? with Answer - Chemical Engineering Mcqs | TestPrep

> Solved MCQ: What is the critical rotation speed in revolutions per second, for a ball mill of 1.2 m diameter charged with 70 mm dia balls ? Correct Answer: D. 0.66. Verified answer explanation for FPSC, PPSC, MDCAT, NTS, and CSS competitive exam preparation.

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# What is the critical rotation speed in revolutions per second, for a ball mill of 1.2 m diameter charged with 70 mm dia balls ?

Direct Answer & Quick Reference

The correct option is **D. 0.66**.

A. 0.5

B. 1.0

C. 2.76

D. 0.66 **(Correct Answer)**

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Verified Key: D. 0.66
Solved by 2,962+ students

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