Torsion formula terminology: identify J/R in the torsion equation Using the torsion relation T/J = τ/R = Gθ/L for circular shafts. State the standard name of the quantity J/R. Choose the correct term.
Mechanical Engineering
Strength of Materials
Difficulty: Easy
Choose an option
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AShear modulus
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BSection modulus
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CPolar modulus (polar section modulus)
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DNone of these
Answer
Correct Answer: Polar modulus (polar section modulus)
Explanation
Concept/FormulaFor circular shafts in torsion: T/J = τ/R = Gθ/L.Here, J is polar moment of inertia and R is outer radius. The ratio J/R is called the polar modulus (or polar section modulus), a geometric property indicating torsional strength.
Final AnswerPolar modulus (polar section modulus).