Question

The allowable static stress for steel gears is approximately ____________ of the ultimate tensile stress.

(a) one-fourth

(b) one-third

(c) one-half

(d) double

This question was addressed to me by my college professor while I was bunking the class.

I want to ask this question from Spur Gears topic in chapter Toothed Gearing & Gear Trains of Machine Kinematics

Answer 1

The correct answer is (b) one-third

The explanation: The allowable static stress (σo) for steel gears is approximately one-third of the ultimate tensile strength

(σu) i.e. σo = σu / 3.