Polar Moment of Inertia Calculator for Circular Shafts

Calculate Polar Moment of Inertia

Utilize our free Polar Moment of Inertia Calculator to determine the torsional rigidity of circular shafts quickly and accurately. This essential tool helps mechanical engineers and designers assess a shaft's resistance to twisting, crucial for preventing failure under torsional loads. Calculate for both solid and hollow circular sections with ease.

Formula:

Formulas for Polar Moment of Inertia

The polar moment of inertia (J), also known as the second polar moment of area, quantifies an object's resistance to twisting or torsion. It is a critical parameter in the design of shafts and other components subjected to torsional loads.

  • For a Solid Circular Shaft:
  • J = (π/32) * D4

  • For a Hollow Circular Shaft:
  • J = (π/32) * (Do4 - Di4)

Where:

  • J = Polar Moment of Inertia (e.g., mm4, in4)
  • π = Pi (approximately 3.14159)
  • D = Diameter of the solid circular shaft
  • Do = Outer diameter of the hollow circular shaft
  • Di = Inner diameter of the hollow circular shaft

Physics and Engineering Tools

Angle of Banking : Design Safe Banked Curves

Go to Calculator

Angle of Repose : Determine Material Slope Stability

Go to Calculator

Annual Average Daily Traffic (AADT)

Go to Calculator

Axial Stress of Cylinder Wall & Tube

Go to Calculator

Beam Deflection for Solid Rectangular Beams

Go to Calculator

Beam Load : Analyze Beam Deflection, Bending Moment & Shear Force

Go to Calculator