Question

Consider the torsion equation given below.

$\frac TJ=\frac{\tau}{R}=\frac{G\theta}{L}$

What the term J/R represents in the above equation?

• A. Section modulus
• B. Polar modulus
• C. Shear modulus
• D. None of these

Answer 1

Answer:

B. Polar modulus

The term J/R in the torsion equation represents the polar modulus of a bar. It is obtained by dividing the polar moment of inertia of the bar (J) by its radius (R). The polar modulus is a measure of a bar's resistance to torsion.