Page 119 - ACTIVE SCIENCE 4 TOC

Pulley : A pulley is a machine with a
wheel. It has two raised edges so that a

rope or a string can run along with the Pulley
wheel without dropping off. It is used to

draw, pull or raise things. For example,
a pulley is used to draw a bucket of

water from the well. Pulley

Inclined Plane : It is a sloping surface
on which we can push an object up or

down. For example, loading heavy Inclined Plane

things on to a truck, is done by an
inclined plane.

Wheel and Axle : The wheel and axle

allows movement of larger objects over
a distance with less force. There are two

wheels in the front or the back of the Axle
vehicle with a rod between them. The Wheel

rod is called the axle which works as a
connector. The wheels and axle moves

simultaneously.

Wedge : Wedge is a triangular shaped

tool. It has a slanting surface and a Wedge
sharp edge in front and blunt at the

back. It is used to separate two objects.
For example, an axe is used to cut wood.

Screw : It is a cylindrical-shaped tool

with a sharp edge and a blunt circular
top. It is an inclined plane with a raised

line around a straight rod. It is used
to join or attach things. It is used in Screw

furniture and doors to fix them.

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