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3. Third Class Lever: When the effort is in between the fulcrum and the load, it is a
third class lever. Examples are ice tongs, fishing rod, forceps, etc.

Ice tongs Fishing rod Forceps

Pulley

A Pulley is a simple machine made up of a wheel and a rope. The rope fits into the
wheel and one end of the rope is attatched to the load. When you pull on one side
of the pulley, the wheel turns and the load moves.

Pulley helps to move load up,
down and sideways. It makes
the load work easy. In a pulley
an effort can be applied in one
direction and a load can be
moved in another direction.
Pulley can do twice as much
work with the same effort.

Crane Pulley

Inclined Plane

The inclined plane is simply a ramp or flat, sloping
surface. One end is higher than the opposite end.
This allows things to go from a low place to a higher
place. It is used to move heavy load to certain height,
e.g., loading heavy drums or boxes to the truck. Less

effort is needed to move the object with an inclined plane as compared to a steep
slope.

Screw

A screw is a simple machine made up of another simple machine. It is an inclined
plane wrapped around a cylinder. It has ridges or threads that change the direction of

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