26) The radial distance of a tooth from the pitch circle to the bottom of the tooth is called

27) When the crank is at the inner dead centre, in a reciprocating steam engine, then the velocity of the piston will be

28) The gears are termed as medium velocity gears, if their peripheral velocity is

29) The frequency of damped vibrations with viscous damping is __________ the frequency of undamped vibrations.

30) Whitworth quick return motion mechanism consists of three turning pairs and one sliding pair.