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Levers
Level 1 Physical Education
Pakuranga College 2011
Leve
rs
Levers are simple machines
made up of a pivot (fulcrum),
effort, and resistance (load)
arm.Levers help apply force.
Longer levers result in greater
speed. Good for throwing &
striking.Shorter levers result in greater
strength. Good for pulling,
pushing and lifting.The most common lever found in
the human body is the 3 rd class lever
Com
ponents
of
a
leve
r
Fulcrum – the pivot
point around which the movement happens.Load – The weight
that needs to be moved.Effort – The place
where the force is applied. In the body this is the
effort produced by the contracting
muscles.
Leve
rs in
the
hum
an b
ody
Levers are made up of
the joints (fulcrum), and the bones that connect them to the
objects being moved.
Levers in the human
body can be manipulated to improve speed, and apply large forces at
the same time.
Firs
t C
lass
Leve
r
These levers can help
to either increase force or generate more speed depending
on the position of the
fulcrum.
1st class body example:
Seco
nd C
lass
Le
ver These levers allow
more force to be produced because the effort arm, is longer than the resistance arm.
2nd class lever examples: running and press-ups
2nd class body example:
Thir
d c
lass
leve
rThird class levers
generate speed rather than force
3rd c
lass
exa
mple
s:
hock
ey
stic
k and
base
ball
bat
3rd c
lass
exa
mple
s co
nt.
: ka
yaki
ng a
nd
div
ing b
oard
3rd class body example
How
can w
e
rem
em
ber
these
le
vers
?
FLE 123This Statement shows
what element is in the
middle: Fulcrum is in the middle
in 1st class levers Load is in the middle in
2nd class levers Effort is in the middle in
3 rd class levers
Pract
ical L
ab
Here's what you'll need:• a 30 cm plastic ruler• 10 objects of varying weights• a pencil/pen• a level desk or table
top
Pract
ical L
ab
Create each of the 3
classes of lever using
the various pieces of
equipment allowed.
1st, 2
nd , 3
rd c
lass
le
ver
exam
ple
s
