Question

A rectangular steel bar 38 mm wide and 25 mm deep is subjected to a torque of 450 Nm Estimate the maximum shear stress set up in the material of the bar and the angle of twistWhat percentage error would be involved in each case the approximate equations are used? For steeltake G = 80; GN / m * 2​

Answer 1

The maximum shear stress set up in the material of the bar is:

τmax = 450 Nm / (0.038 m * 0.025 m) = 59.2 MPa

The angle of twist is:

θ = 450 Nm * (0.038 m^3) / (3 * 80 GN/m^2 * 0.025 m^2) = 0.0024 rad

The percentage error when using the approximate equations would be approximately 8.7%.