Slip of belt:

Sol:  When the driver pulley rotates, it carries belt, because of a firm grip between its surface and belt. The firm between pulley and belt can be obtained by friction. This firm grip is called as frictional grip. But sometimes frictional grip is not enough. This can cause forward motion of the driver pulley without carrying belt with it. This means that there is relative motion between driver pulley and belt. The difference between linear speeds of pulley rim and belt is measure of slip. In general, the slip is expressed as percentage. In some of the cases, the belt moves faster in forward direction, without carrying the driver pulley with it. Hence in case of driven pulley, forward motion of belt is more than that of the driver pulley.

Slip of belt can be usually expressed in percentage.

Let v = Velocity of belt, passing over driver pulley/min

N₁ = Speed in round per minute of driver

N₂ = Speed in round per minute of follower

S₁ = Slip between driver and belt in %

S₂ = Slip between follower and belt in %

The peripheral velocity of driver pulley

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