Project ForgeStrength of Materials
Stress & Strain
GATE 2007
Medium
A stepped steel shaft, φ50 mm over 100 mm length then φ25 mm over a further 100 mm length, is subjected to 10 Nm torque. If the modulus of rigidity is 80 GPa, the strain energy in the shaft in N·mm is
- A4.12
- B3.46
- 1.73
- D0.86
Explanation
J₅₀=π(50)⁴/32≈613,592 mm⁴; J₂₅=π(25)⁴/32≈38,349.5 mm⁴. U=ΣT²L/(2GJ) with T=10,000 N·mm, G=80,000 N/mm²: U₅₀≈0.102 N·mm, U₂₅≈1.630 N·mm, total ≈1.73 N·mm.
Source: GATE ME 2007 (2007)
This question is part of a 15-day revision cycle — sign in and Project Forge will bring it back the day before you'd forget it.