External and internal radius of collar)
A. (μπ²N/60t) × (R₁ - R₂)
B. (μπ²N/60t) × (R₁² - R₂²)
C. μπ²N/60t) × (R₁³ - R₂³)
D. (μπ²N/60t) × (R₁⁴ - R₂⁴)
Answer:A
External and internal radius of collar)
A. (μπ²N/60t) × (R₁ - R₂) B. (μπ²N/60t) × (R₁² - R₂²) C. μπ²N/60t) × (R₁³ - R₂³) D. (μπ²N/60t) × (R₁⁴ - R₂⁴)