Theory of Structures - Engineering

Q1:

If a solid shaft (diameter 20 cm, length 400 cm, N = 0.8 x 105 N/mm2) when subjected to a twisting moment, produces maximum shear stress of 50 N/mm2, the angle of twist in radians, is

A 0.001

B 0.002

C 0.0025

D 0.003

E 0.005

ANS:C - 0.0025

We know,

Shear stress/radius = G * angle of twist/L.
So, 50/100=(0.8*10^5)*theta/4000.

From the above equation after solving we will get the value of the angle of twist i.e.
θ = 0.0025.

I have converted the value of Dia to Radius (R=100mm).

So, option (C) is correct.