Kinesiology chapter 8

Friction: force that prevents motion

Two or more forces must act on a common point but must pull or push in different directions

A simple pulley attached to a beam. 1st-class lever used only to change direction

A rigid bar around which a movement occurs around an axis (bone)

Putting a weight cuff in which position would require more effort at shoulder joint to move cuff through shoulder ROM?

refers to the amount to the amount of matter that a body contains

any change in the velocity of an object. (how far a ball goes depends on how hard you kick it)

When your driving car in motion and stop suddenly and your body is thrown forward and neck goes into flexion. What law?

Most common, designed for range of motion.

Taking the principles and methods of mechanics and applying it to the human body

dislocating force is the force directed away from the axis

Deals with the manner in which adjoining joint surfaces move in relation to each other,in the same or opposite direction

Torque, also known as moment of force is the ability of force to produce rotation around an axis

Occur in the same plane and in the same or opposite direction

Nearly all the force generated by the muscle is directed back into the joint, pulling the 2 bones together.

Statics/ Dynamics

Law of action/reaction: For every action there is an equal and ______ reaction.

Forces causing movement, movement created by force

Objects at rest stay at rest & objects in motion stay in motion. Resistance to change speed or direction

When you jump down on the floor off a small step, you can feel this force traveling up through your legs

Which of the following is not one of Newton's laws of motion?

Center of gravity (COG): is the balance point of an object at which torque on all sides is ______.

Law of acceleration: Amount of acceleration depends on the ______of force applied to it.

A vector that describes speed and is measured in units such as feet per second or miles per hour.

describes magnitude (length, area, volume, and mass)

Wheel and axle: passive shoulder rotation: joint is axle, forearm is wheel

inclined plane, flat surface that slants.

Movement force, most of the force generated by te muscle is directed at rotating, not stabilizing, the joint

Branch of physics dealing with the study of forces and the motion produced by their actions

Neutral equilibrium exists when an object's COG is neither raised nor lowered when it is disturbed.

The manner in which bones move in space

Occcurs when only a slight force is needed to ditrurb an object

Force arm (FA) is the distance between the force and axis. Resistance arm (RA) distance between resistance and axis

The fixed point around which the lever rotates (joint)

When an object is balanced, all torques acting on it are even

Force (F) causes lever to move (muscle). Resistance (R), (weight, gravity)Must be overcome in order to move

The property of matter that causes it to resist any change of its motion in either speed or direction

Perpendicular distance from force's line ofpull to axis (muscle's line of pull to joint)

force is applied closer to axis than the resistance, smaller amounts of resistance moved by larger amounts of force

Has one end of the rope attached to the beam; the rope runs through the pulley to the other end.

tendency of force to produce rotation around an axis

Parallelogram method: diagonal represents the resultant force, resultant force of unequal forces moves toward the ______

A push or pull action that can be represented as a vector

axis lies between the force and the resistance, requires balance (ruler, pencil, book)

Jumping down on trampoline, trampoline pushing back w same amount of force, causing you to rebound in opposite direction

3 states of equilibrium: occurs when an object is in a position where disturbing it would require its COG to be raised

Results when two or more forces are acting along the same line

Having both magnitude and direction. (ex. pushing something a certain speed and direction)

Consists of a grooved wheel that turns on an axle with a rope or cable riding in the groove

Imaginary vertical line passing through the COG toward the center of the earth

occurs when two or more forces act in different directions, resulting in a turning effect.

large weights can be moved by small amount of force, resistance is closer to axis than force. (wheelbarrow)