Levers of Movement Flashcards
What are the components of a lever?
Lever arm
Fulcrum (Pivot)
Load
Effort
What is a lever?
A lever is a system that magnifies force. It is a rigid system.
What order is the effort, axis and load in a 1st class lever
The effort and load are on opposite side of the axis.
Do the forces act in the same or opposite direction on a 1st class lever?
The same
What are some examples of a 1st class lever?
See saw, neck
What order is the effort, axis and load in a 2nd class lever?
Effort and load are on the same side of axis. Axis at one end, load in the middle, effort on the other end.
Do the forces act in the same or opposite direction on a 2nd class lever?
Effort and load forces work in opposite directions.
What are some examples of 2nd class levers?
Calf raises
What is the 2nd class lever good for?
Good for strength application but not for moving load at high velocity or through large range of movement.
What order is the effort, axis and load in a 3rd class lever?
Effort and load are on the same side of the axis. Axis at one end, effort in the middle and load at the other end.
Do the forces act in the same or opposite direction on a 3rd class lever?
Effort and load forces act in opposite directions
What is the 3rd class lever good for?
Good for moving a load at high velocity and through a large range of movement but it is poor for strength application.
What are examples of a 3rd class lever?
Bicep curl, hamstring curl
Define Moment arm
The perpendicular distance from an axis to the line of action of force. It is always 90 degrees to the line of action and passes through the axis of rotation.