Explanation: Worm gears are used where large speed reductions are needed. The horizontal portion of the gear is called as a worm and the assembly of it with the gear is known as a worm gear. Worm can easily turn a gear but a gear cannot turn a worm because of the shallow angle on the worm.

Explanation: Reduction of speed and increasing the torque is an advantage of worm gear. The rest are the disadvantages of the worm gear. Worm gears are used in gate control mechanisms, hoisting machines, automobile steering mechanisms, lifts, conveyors and presses.

Explanation: Lead is the distance by which a helix advances along the axis of the gear for one turn around. The axial pitch is equal to the lead in a single helix and the axial pitch is one half of the lead in a double helix and so on.

Explanation: By geometry of bevel gears, it is evident that they are equivalent to rolling cones. Their pitch surface is a cone. Bevel gears exist as pairs which can be either straight or inclined at different angles.

Explanation: Bevel gears increase the contact ratio. It avoids interference and results in stronger pinion teeth. The gear ratio can be determined from the number of teeth, pitch diameters or pitch cone angles.

Explanation: In a centrifugal clutch, ω is the angular running speed of the body. ω1 is the angular speed at which the engagement begins to take place.

Explanation: Centrifugal clutches are incorporated into motor pulleys which consist of a number of shoes on inside of the rim of the pulley. These clutches are generally incorporated into the motor pulleys. The outer surfaces of the shoe are covered with a layer of a friction material.

Explanation: In a centrifugal clutch, ω is the angular running speed of the body. ω1 is the angular speed at which the engagement begins to take place.

Explanation: In a multi plate clutch, number of discs on the driving shaft is given by n1, whereas number of discs on the driven shaft is given by n2. With the help of these two variables we can find out the number of pairs of contact surfaces.

Thus, the axial thrust = 1250 N.