Page 38 - Science Class 6 Times Publication

Combined pulley

A pulley which consists of a combination of two or more pulleys is
called combined pulley. A combined pulley is also called compound
pulley or block and tackle.

Wooden disk Fixed pulley

Rope

Movable pulley
E

L

Combined pulley
3. Wheel and axle

A wheel and axle is a simple machine which consists of two wheels
(cylinders) of different diameters. The larger cylinder or wheel is

xed rigidly with the small wheel in such a way that both the wheels
spin about the same axis. Generally, load is lifted by the small wheel
and the effort is applied on the big wheel.

Wheel

Wheel
Axe Axe

Wheel
screw driver Kite string reel Steering of car

Door knob, wheel of vehicle, steering of a vehicle, screw driver, etc
are the examples of wheel and axle.

Times' Crucial Science and Environment 34 Book 6