The contact ratio for gears is ______.

Interference can be avoided in involute gears with 20° pressure angle by ______.

For a speed ratio of 100, the smallest gearbox is obtained by using a ______.

The gears are termed as medium velocity gears if their peripheral velocity is ______.

The radial distance of a tooth from the pitch circle to the top of the tooth is called ______.

The working depth of a gear is the radial distance from the ____.

The radial distance from the top of a tooth to the bottom of a tooth in a meshing gear is called ______.

When two spur gears having involute profiles on their teeth engage, the line of action is tangential to the ______ circles.

If the annular wheel of an epicyclic gear train has 100 teeth and the planet wheel has 20 teeth, the number of teeth on the sun wheel is ______.

In a simple gear train, if the number of idle gears is odd, then the motion of driven gear will _____.