## Theory of Machine The frictional torque transmitted in a flat collar bearing, considering uniform wear, is (where r₁ and r₂ = External and internal radii of collar respectively)

(1/2) μ W [(r₁³ - r₂³)/(r₁² - r₂²)]
(2/3) μ W (r₁ + r₂)
(1/2) μ W (r₁ + r₂)
(2/3) μ W [(r₁³ - r₂³)/(r₁² - r₂²)]

## Theory of Machine The lower pair is a

Sliding pair
Open pair
Point contact pair
Closed pair

2πk/r. √(g/l)
r/2πk. √(g/l)
2πr/k. √(g/l)
r/2πk. √(l/g)

Pitch circle
Prime circle
Root circle
Base circle

## Theory of Machine The working depth of a gear is the radial distance from the

Pitch circle to the bottom of a tooth
Addendum circle to the clearance circle
Pitch circle to the top of a tooth
Top of a tooth to the bottom of a tooth

## Theory of Machine The velocity of the reciprocating roller follower when it has contact with the straight flanks of the tangent cam, is given by (where ω = Angular velocity of the cam shaft)

ω (r₁ r₂) cosθ
ω (r₁ + r₂) sinθ sec2θ
ω (r₁ + r₂) cosθ cosec2θ
ω (r₁ r₂) sinθ