Thames & Kosmos Alien Robots, Руководство по эксперименту

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7
› › › CHECK IT OUT
››› Look for levers
in the models you
build!
Alien Robots
THE FORCES ON A LEVER
The fulcrum is the spot on the bottom
of the anchor pin lever that doesn’t
move when the tool is used to pry up
a pin. The two arms pivot around this
point.
Load Arm and Force Arm
When you press on the handle with
enough effort force for the anchor
pin to come out of its hole, the part
separator tool is in a state of balance
or equilibrium in its work. The arm of
the lever on the effort side is longer
in proportion to the degree that the
effort force is smaller. The opposite
happens on the load side. The load
arm is shorter in proportion to the
degree that the load force is greater.
If the effort arm is twice as long as
the load arm, then there is a balance
when the effort force is half as great
as the load force. Effort force (kg)
times the distance on the effort arm
from the exertion point of the effort
force to the fulcrum (m) is equal to
load force (kg) times the distance
from the load force to the fulcrum
on the load arm (m). Written a little
differently, this is how the equation
goes:
effort force x effort arm length
=
load force x load arm length
Force
Fulcrum
Load
Diagram: Lever
Large load
force
Small load
force
Load force
line of action Effort force
line of action
Exertion point
of effort force
Exertion point
of load force
Fulcrum
Load arm
Effort arm