Lecture #3 Flashcards
1
Q
What are 3 types of machines that produce movement?
A
- Levers (most common)
- Wheel-axles
- Pulleys
2
Q
What is a lever?
A
A ridged bar that turns about on an AXIS of rotation (fulcrum)
3
Q
What is an AXIS?
A
Point of rotation about which lever moves
4
Q
What are 3 points to determine type of lever and which motion is best suited?
A
- Axis (A) Fulcrum:point of rotation
- Force (F): usually muscle insertion
- Resistance (R): Center of gravity of a lever
5
Q
What is a first class lever? What does it produce and example in body
A
- FAR
- Produces speed
- Triceps in elbow extension
- Nodding of the head
6
Q
What is a second class lever? What does it produce and example
A
- ARF
- Produces force
- Gastrocs when standing on toes
7
Q
What is a third class lever? What does it produce and example
A
- AFR (most common)
- Produces ROM
- Biceps brachii
- Hamstrings
8
Q
What doe pulleys do? Example?
A
They change the direction of force
EX: Lateral malleolus is a pulley
9
Q
How do you calculate force?
A
F = m x A
-Weight of gravity X acceleration
10
Q
What are some examples of force tissues can go through?
A
- Tension (stretching)
- Compression
- Shearing (opposite forces)
- Bending
- Torsion (twisting)
11
Q
What is the inervation of serratus anterior?
A
Long throasic nerve
