English
( EN )
Experiment #1
Balancing the Balance
Objectives: Investigate how the
closeness of the resistance to the
fulcrum affects the effort needed to
achieve a state of balance.
Materials You Will Need:
built BALANCE model
10 washers or small paper clips
Small stickers or pieces of masking tape
A small object such as a binder clip, an eraser
or a piece of chalk
paper or notebook
ruler
PROCESS:
1. Build the BALANCE model by following the step-by-
step building instructions.
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Education
79319
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2. Using small stickers or
pieces of masking tape,
identify the fulcrum, load,
and effort of the balance
model.
3. Identify which class of
lever the balance belongs
to and why.
a. Remove the gray trays (gray pulley wheels) from
the model. Push the red and orange hangers to
the end of the balance arms. Once the two arms
are stationary, observe and describe, using the
correct vocabulary, what the model is doing.
b. What happens when one end of the model is
given a small push/has a force applied? Explain
your observations.
c. Why does the balance remain stationary, or at
rest, until a force acts on it?
4. Replace the hanging trays (gray pulleys) so that there
are two (2) pulleys on one side and one (1) pulley
on the other. Push both of the hanging trays (gray
pulleys) to the end of the balance arms.
For printer friendly versions of the experiments, go to:
fulcrum
load
effort
and enter the code
www.knex.com/instructions
79319.
