Chapter 2 Flashcards
(26 cards)
What is a lever
A rigid bar that turns about an axis to create movement
What do all levers contain
- fulcrum
- load
- effort
What is a fulcrum
Fixed point at which a lever turns or is supported
What is the load
The weight that the lever must move
What is an effort
The force required to move the load
Examples of a first class lever
Raising your head - header in football
Throw ball over head - line out in rugby
Example of a second class lever
- rising onto your toes
- push up
What is a high mechanical advantage
- when the effort arm is longer that the load arm
- move large loads with low effort
What is the mechanical advantage equation
Mechanical advantage = effort arm/load arm
What is the mechanical advantage
The efficiency of a lever
What is the effort arm
Distance from the effort to the fulcrum
What is the load arm
Distance from the load to the fulcrum
Example of a third class lever
- bicep curl
- paddling a kayak
What is flexion
When the angle of the bones at the joint decreases
What is extension
When the angle of the bones at the joint increases
What is abduction
The movement of the limb away from the midline of the body
What is adduction
When the limb moves towards the midline of the body
What os dorsiflexion
Takes place at the ankle joint when the foot flexes up
What is plantar flexion
When the foot flexes downwards
What is rotation
Circular movement where part of the body turns while the rest remains still
What is a plane
A line drawn through the body dividing it into two parts
What occurs at a plane
Movement
What are the types of planes
- frontal plane
- transverse plane
- sagital plane
What happens on an axis
Rotation
