Kin Biomechanics

Question 1

Force

Answer 1

Push or pull action that can be represented as a vector

Question 2

vector

Answer 2

quantity that has both magnitude and direction

push a wheelchair, one pushes it with a certain speed and certain direction

Question 3

velocity

Answer 3

vector that describes speed and is measured in units such as f/s or m/h

Question 4

scalar

Answer 4

quantity that measures only magnitude

like length, area, volume, and mass

Question 5

mass

Answer 5

amount of matter that a body contains

Question 6

inertia

Answer 6

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

Question 7

Is mass a measure of inertia?

Answer 7

yes, its a measure of its resistance to a change in motion

Question 8

torque

Answer 8

tendency of force to produce rotation around an axis

Question 9

friction

Answer 9

a force developed by two surfaces, which tends to prevent motion of one surface across another.

Question 10

3 laws of Newton

Answer 10

Law of inertia
Law of acceleration
Law of action reaction
(iaa)

Question 11

Law of inertia

Answer 11

an object at rest tends to stay at rest and an object in motion tends to stay in motion

Question 12

Law of acceleration

Answer 12

the amount of acceleration depends on the strength of the force applied to an object
(how fast it go, depends on how hard it hit!)

Question 13

Law of action reaction

Answer 13

for every action there is an equal and opposite reaction

Question 14

Linear force

Answer 14

two of more forces are acting along the same line

Question 15

parallel forces

Answer 15

occur in the same plane and in the same or opposite direction.

Question 16

concurrent forces

Answer 16

two or more forces acting on common point but will be pushing or pulling in different directions

Question 17

The overall effect of two different forces

Answer 17

The resultant force

Question 18

The parallelogram method

Answer 18

Approach used to determine the resultant force

Question 19

Force couple

Answer 19

a turning effect from two or more forces acting in different directions
scapula rotating from serratus ant., and the upper and lower traps

Question 20

Moment of force

Answer 20

Torque, or angular force

Question 21

the twisting forces ( moment of force, or torque ) of a wrench can be increased by

Answer 21

increasing the force applied to lever

increasing the length of the handle

Question 22

Moment arm (torque arm)

Answer 22

perpendicular distance from a forces line of push/pull to the axis of rotation

Question 23

process of stabilizing, dislocating, and greatest force

Answer 23

at 90 degrees - greatest force
nearing 0 degrees - stabilizing force
moving beyond 90-180 degrees - dislocating force

Question 24

state of equilibrium

Answer 24

all torques acting on object are even and balanced

Question 25

gravity

Answer 25

mutual attraction between an object and earth

Question 26

COG

Answer 26

point at which all planes of body intersect, or balance point of an object at which torque on all sides is equal

Question 27

BOS

Answer 27

part of a body that is in contact with the supporting surface

Question 28

LOG

Answer 28

imaginary vertical line from the COG toward the center of earth

Question 29

stable equilibrium

Answer 29

object is in a position where disturbing it would require its COG to be raised

Question 30

unstable equilibrium

Answer 30

only a slight force is needed to disturb an object

Question 31

neutral equilibrium

Answer 31

objects COG is neither raised nor lowered when it is disturbed. Soccerball

Question 32

lever

Answer 32

rigid and can rotate around a fixed point when a force is applied

Question 33

axis, force, resistance

Answer 33

axis - the fixed point around which the lever rotates force - effort that causes the lever to move resistance - load that must be overcome

Question 34

Force arm

Answer 34

the distance between the force and the axis

Question 35

Resistance arm

Answer 35

the distance between the resistance and the axis

Question 36

First class lever

Answer 36

F__________________R | A

Question 37

second class lever

Answer 37

R F _____________________ A

Question 38

third class lever

Answer 38

F R _____________________ A