Question

When effect of friction is negligible, the force is transmitted by the link from driver to the driven link through the centre line of the pins connecting the link. With friction, the line of action shifts and is tangent to _____________

(a) kinetic friction

(b) dry friction

(c) friction circle

(d) none of the mentioned

I got this question during an internship interview.

Asked question is from Limiting Angle of Friction topic in section Friction of Machine Kinematics

Answer 1

Correct answer is (c) friction circle

For explanation: When effect of friction is negligible, the force is transmitted by the link from driver to the driven link through the centre line of the pins connecting the link. With friction, the line of action shifts and is tangent to friction circle.

When the load on the rubbing surfaces is carried partly by a fluid viscous film and partly by areas of boundary lubrication, it is known as incomplete lubrication.