LINEAR TRANSMISSION OF MOTION

Levers

A lever is a rigid bar that truns around  point called fulcrum. Various forces may act on the lever at the same time. When the forces acting on opposite ends of a lever are equal, we say the lever is in equilibrium. We can express this mathematically as the Law of the Lever:

                                       F x d = R  x r                            

CLASSES OF LEVERS

A HAND CRANK

It has two parts, one is connected to a rotating shaft and the other forms a handle. We can use a hand crank to apply force at a distance from the axis of the shaft. It has the Law of the Lever.

Class 2 lever

PULLEYS AND COMPOUND OF PULLEYS SYSTEMS

In a system of pulleys, equilibrium between the forces depends on the path that the rope follows.

PULLEYS

A pulley is a wheel that rotates around an axis and has a groove. We use this mechanism to apply less force. There are two basic pulleys:

Fixed pulley (F=R)

Movable pulley (F=R/2)

                                                     

COMPOUND PULLEY SYSTEMS

This is a special combination of fixed and movable pulleys.The more pulleys we have, the mechanism is more complex, but  it is easier to lift the load.

    

  Vertical and Exponential systems

Horizontal System