c (m - M) g
c (m + M) g
c/(m + M) g
c/(m - M) g

## Theory of Machine When there is a reduction in amplitude over every cycle of vibration, then the body is said to have

Damped vibration
Under damped vibration
Forced vibration
Free vibration

Prime circle
Base circle
Pitch circle
Pitch curve

## Theory of Machine The method of direct and reverse cranks is used in engines for

Kinematic analysis
Vibration analysis
The control of speed fluctuations
Balancing of forces and couples

## Theory of Machine When the addenda on pinion and wheel is such that the path of approach and path of recess are half of their maximum possible values, then the length of the path of contact is given by (where r = Pitch circle radius of pinion, R = Pitch circle radius of wheel, and φ = Pressure angle)

[(r + R) cosφ]/2
[(r + R) sinφ]/2
[(r² + R²) cosφ]/2
[(r² + R²) sinφ]/2

## Theory of Machine It is required to connect two parallel shafts, the distance between whose axes is small and variable. The shafts are coupled by

Universal joint
Oldham's coupling
Knuckle joint
Flexible coupling