Part 2 Flashcards
What is Internal Force
force created by muscles
What is force?
energy that causes movement and has direction and magnitude. F=m x a
What isExternal Force?
outside forces acting on a body. Example: gravity, opposing player
What is Newton’s first law of motion ?
body at rest tends to stay at rest, body in motion tends to stay in motion (inertia)
What is newtons second law of motion
acceleration of an object directly proportional to the force causing the motion, and inversely proportional to the mass of the object (acceleration and momentum)
What is Newton’s third law of motion ?
for every action there is an equal and opposite reaction
What is Center of Gravity?
point of which a body is balanced
What is Line of Gravity?
vertical line thru the center of gravity
What is Base of Support?
2-dimension area between an object’s points of contact
What is Stability?
occurs when line of gravity falls within base of support
What is Lever arm is
the distance from the axis of rotation to the line of action of the force
What is Active insufficiency?
the muscle is incapable of shortening any further.
Passive insufficiency?
the muscle is elongated over the joints it crosses, the antagonist cannot shorten any more
Elasticity:
ability of tissue to resume former shape after a deforming force is applied then released
Stiffness:
ability of tissue to resist deformation when stress is applied to it
