The frictional torque transmitted in a flat collar bearing, considering uniform wear, is (where r₁ and r₂ = External and internal radii of collar respectively)

A. (1/2) μ W (r₁ + r₂)

B. (2/3) μ W (r₁ + r₂)

C. (1/2) μ W [(r₁³ - r₂³)/(r₁² - r₂²)]

D. (2/3) μ W [(r₁³ - r₂³)/(r₁² - r₂²)]

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