LEVERS Investigation

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LEVERSInvestigation 1
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A lever is a simple machine that people use to
gain mechanical advantage.  It has a fulcrum for
the lever arm to pivot from.  The load is placed
on the lever arm and effort is applied to lift
the load. 
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What are the four parts of a lever system?In
what ways can a lever provide an advantage?
ANSWER
ANSWER
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Basic Procedures for Operating a Lever

•   Zero the spring scale.
•   Level the lever arm.
•   Place the load and effort on the lever
  arm.
•   Pull spring scale until lever arm is level
•   Read scale indicator at eye-level 
•   When finished, place load and scale on the
  table.

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How much effort is needed to lift our load? 
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Why would you use a machine to lift a load?
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How do you know when you are gaining mechanical
advantage?
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Our load requires 2.4N to be lifted, so
mechanical advantage is gained when less than
2.4N are needed to lift the load. 2.4N is the
STANDARD to which we will compare the outcomes of
our controlled experiments.
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What are the possible variables that we can
manipulate in a controlled experiment of a lever?
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CONTROLLED EXPERIMENT 1of the LEVER SYSTEM

• VARIABLE We will change the position of the
  effort on the lever arm.

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Write a prediction in your journal of how
changing the position of the effort may affect
the standard outcome.
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Did the lever give any advantage in lifting the
load?Did the amount of force needed to lift the
load change when you moved the position of the
effort?
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What is the relationship between the position of
the effort and the amount of effort needed to
lift the load? The two-coordinate graph can
help you see this relationship.
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We can change the mass of the load.
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We can change the position of the load.
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We can change the position of the effort.
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We can change the length of the lever arm.
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We can change the position of the fulcrum.
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The four parts of the lever are the lever arm,
fulcrum, load, and effort.
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A lever can make a load easier to lift.
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2.4N are needed to lift our load.
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Because it would be easier.
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When the effort needed to lift the load is less
than 2.4N.
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The farther the effort is from the fulcrum, the
easier the load is lift the closer the effort is
to fulcrum, the harder it is to lift the load.