n₁ + n₂ - 1
n₁ + n₂
n₁ + n₂ + 1
n₁ + n₂ - 2

## Theory of Machine The factional torque for square thread at the mean radius r while raising load W is given by

T = W.r tan(φ + α)
T = W.r tanφ
T = W.r tanα
T = W.r tan(φ - α)

## Theory of Machine For S.H.M. cam, the acceleration of the follower at the ends of the stroke and aimed stroke respectively, is

Zero and maximum
Zero and minimum
Maximum and zero
Minimum and maximum

## Theory of Machine The mechanism in which two are turning pairs and two are sliding pairs, is called a

Scotch yoke mechanism
Elliptical trammel
All of these
Double slider crank chain

## Theory of Machine The centre of gravity of a coupler link in a four bar mechanism will experience

Both linear and angular acceleration
Only angular acceleration
Only linear acceleration
No acceleration

## Theory of Machine The contact ratio is given by

(Length of path of recess)/(Circular pitch)
(Length of the path of approach)/(Circular pitch)
(Length of the arc of approach)/cosφ
(Length of the arc of contact)/(Circular pitch)