Download Aptitude Crack
img not found img not found

UPSC Civil Service Exam Questions - Engineering

Q1:

A close-coiled helical spring has 100 mm mean diameter and is mada of 20 turns to 10 mm diameter steel wire. The spring carries an axial load of 100 N Modulus of rigidity is 84 GPa. The shearing stress developed in the spring in N/mm2 is

A 120/π

B 160/π

C 100/π

D 80/π

ANS:D - 80/π

=> 16T/pi D*3.
T = PD/2 or PR
= 16PR/π D*3.
= 16*100*50/π10^3.
= 80/π.