Question

If the angle of contact is greater than 60 degrees, then unit pressure normal to the surface of contact is __________

(a) Less at the ends than at the centre

(b) More at the ends then centre

(c) Remains equal at the ends and the centre

(d) Remains unaffected

I had been asked this question in semester exam.

I need to ask this question from Brakes topic in chapter Brakes and Dynamometers of Machine Dynamics

Answer 1

Correct choice is (a) Less at the ends than at the centre

Explanation: If the angle of contact is greater than 60°, then the unit pressure normal to the surface of contact is less at the ends than at the centre. For less than 60° the pressure is uniform.