Question

For solid shaft subjected to a torque of 18000 Nm having a permissible shear stress of 60 N/mm² the diameter of shaft is
1. 115 mm
2. 121 mm
3. 149 mm
4. 108 mm

Answer 1

Correct Answer - Option 1 : 115 mm

Concept:

Maximum shear stress for solid shaft is given by:

τ_max =  \(\frac{{16{\rm{T}}}}{{{\rm{\pi }}{{\rm{d}}^3}}}\)

Calculation:

Given:

T = 18000 Nm, τ = 60 N/mm²

60 = \(\frac{{16{\rm{}} \times 18000 \times 1000}}{{{\rm{\pi }} \times {{\rm{d}}^3}}}\)

d = 115.17 mm

Therefore, diameter of the shaft is 115 mm.