2. LINEAR TRANSMISSION OF MOTION:
Linear transmission mechanisms,such as pulleys,use linear motion inut to produce linearmotion output.

2.1 LEVERS:
A lever is a rigid bar that turns around a point called a fulcrum.
Each force prodeces a specific torque,which is the force multiplied by its distance from a fulcrum.
 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+d=R+r


CLASSES OF LEVERS:
We can divide levers into classes according to the locations of the fulcrum,force and resistance.

Class2:levers increase the fore that we apply
Class3:levers incrase the distance that the end of the lever moves.
Class1:levers can do both of those things.