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Wheel and axle
An axle goes through the centre of a wheel.
Together they work as a simple rotating
machine that makes it easier to move
something from one place to another.
Machines make tasks easier. They
reduce the effort you need to move
something, or the time it takes. They
work either by spreading the load,
or by concentrating your efforts.
Machines
Gears
Gears are wheels with teeth that
interlock so that one wheel turns
another. They increase speed or force.
Gears on a bicycle affect how much you
must turn the pedal to spin the wheel.
Science and technology
Another type
places the load
between the fulcrum and the
effort (as on a wheelbarrow).
A third type
of lever, shown by
tongs, places the effort between
the fulcrum and the load.
One type
of lever works like
a see-saw with the fulcrum
between the load and the effort.
Levers
A lever is a bar that swivels
on a fixed point or fulcrum
and makes it easier to move
a load. When you move your
end further (the effort), the
load at the other end moves
a short way powerfully.
The pedal turns
a wheel, which
turns a smaller
wheel at a
greater speed.
Try walking
straight up a hill
and then zig-zag your way up.
The winding path works like a
simple machine. It increases the
distance you walk, but
decreases the effort
you use.
H
a
n
d
s
o
n
Name six simple machines.
Effort required
to push down is
needed here.
Fulcrum
Load
Axle
