Chapter 3: Biomechanical Basics Flashcards
1
Q
Levers
A
most common form of machine
rigid bar that turns about an axis of rotation/force against resistance
2
Q
Resistance
A
center of gravity or location of external resistance
3
Q
Force
A
Usually muscle insertion
4
Q
First Class Lever
A
- Axis between Resistance and Force
EX: seesaw, crowbar, triceps in overhead extension, back of neck
5
Q
Second Class Lever
A
- Resistance between axis and force
EX: bottle opener, wheel barrow, gastrocnemius
6
Q
Third Class Lever
A
- Force between resistance and axis
- most common type in body
EX: catapult, screen door opened by a short spring
7
Q
Newton’s First Law
A
Inertia: the resistance to change
more mass = more force needed
8
Q
Newton’s Second Law
A
Acceleration: a change in acceleration happens in the same direction as the force that caused it
9
Q
Newton’s Third Law
A
Reaction: for every action there is an equal and opposite reaction
10
Q
Wheel and Axle
A
wheel and axle turn together
- relatively small force to move large resistance
11
Q
Pulleys
A
Simple pulleys change the direction of an applied force
