Why are there three classes? There are three classes of levers because all are classified by the locations of the fulcrum, the input force, and the output force.
Key Terms: Effort/Input (E)-The force a person uses when they use the lever Load/Output (L)- The force needed to move the object without a lever Fulcrum (F)- the pivot point (i.e. the elbow of an arm)
Second-class levers: In a second-class lever, the effort and load forces are in the same direction.
Why the mechanical advantage is always greater than 1: In a second-class levers the mechanical advantage is always greater than one because the effort arm is always longer than the load arm. In the formula it's MA= effort divided by load which makes it greater than 1.
Example of a second-class lever: a wheelbarrow The fulcrum in the wheelbarrow would be the wheel. The effort force is the hand pushing the wheelbarrow. The load force is the storage space in the wheelbarrow.
A wheelbarrow's Fulcrum is the wheel. The Load sits in the middle, and the Effort is applied on the handles
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Why are there three classes?
There are three classes of levers because all are classified by the locations of the fulcrum, the input force, and the output force.
Key Terms:
Effort/Input (E)- The force a person uses when they use the lever
Load/Output (L)- The force needed to move the object without a lever
Fulcrum (F)- the pivot point (i.e. the elbow of an arm)
Second-class levers:
In a second-class lever, the effort and load forces are in the same direction.
Why the mechanical advantage is always greater than 1:
In a second-class levers the mechanical advantage is always greater than one because the effort arm is always longer than the load arm. In the formula it's MA= effort divided by load which makes it greater than 1.
Example of a second-class lever: a wheelbarrow
The fulcrum in the wheelbarrow would be the wheel. The effort force is the hand pushing the wheelbarrow. The load force is the storage space in the wheelbarrow.