U3 AOS 2: Biomechanics

Question 1

Motion

Answer 1

refers to a body’s change in position in relation to time.

Question 2

Linear motion
(also commonly referred to as translation)

Answer 2

occurs in either a straight line or curved path

Question 3

Angular motion
(also commonly referred to as rotation)

Answer 3

takes place when a body moves along a circular path

Question 4

General motion

Answer 4

is the combination of linear and angular motion

Question 5

Mass

Answer 5

the quantity of matter found within a particular body

Question 6

Inertia

Answer 6

the resistance of a body to a change in its state of motion

Question 7

Force

Answer 7

formula: F=ma

a push or pull on an object or body

Question 8

Distance

Answer 8

the length of space between two points

Question 9

Displacement

Answer 9

the difference between the initial position and the final position of an object

Question 10

Speed

Answer 10

formula: distance / time
OR: linear speed = angular velocity x radius of rotation

time taken to cover a certain distance

Question 11

Velocity

Answer 11

formula: displacement / time

the rate of speed at which an object moves its position

Question 12

(LINEAR) Acceleration

Answer 12

formula: final velocity - (initial velocity) / time

refers to the rate of velocity change experienced by an object over time.

Question 13

Momentum

Answer 13

formula: (p)= mass (m) x velocity (v)

describes the quantity of motion a particular body of mass has

Question 15

Force summation (summation of momentum)

Answer 15

refers to the correct timing and sequencing of body parts to produce maximal force

Question 16

Impulse

Answer 16

formula: force x time

the product of force and time, and is equal to the change in momentum of an object

Question 17

Eccentric force

Answer 17

a force that is off-centre or not directly through an object’s centre of mass

Question 18

Centre of mass

Answer 18

the position where the weight of the object is evenly distributed

Question 19

Torque

Answer 19

formula: force x moment arm

a force that is applied at a distance away from the centre of mass, that causes the object to rotate

Question 20

Angular distance

Answer 20

the angle between the initial and final position of a body/object.

Question 21

Angular displacement

Answer 21

the change of angle between the initial and final position of a body/object

Question 22

Angular speed

Answer 22

refers to the angular distance covered divided by the time taken.

Question 23

Angular velocity

Answer 23

formula: (initial angle - final angle) / time
NEEDS A DIRECTION

the change in angular displacement over time, which indicates how quickly an object rotates

Question 24

Angular acceleration

Answer 24

formula: (final velocity - initial velocity) / time
NEEDS A DIRECTION

is the rate of change of angular velocity (final velocity − initial velocity) over time.

Question 25

Angular momentum

Answer 25

formula: moment of inertia (MOI) x angular velocity (AV) is a measure of how much rotation a body has around an axis

Question 26

Moment of inertia

Answer 26

formula: mass x radius ^2 (radius squared) is a measure of an object’s resistance to change in its rate of rotation

Question 27

Conservation of angular momentum

Answer 27

the principle of conservation of momentum says that while airborne there will be NO change of angular momentum.

Question 28

Newton's first law of motion

Answer 28

Inertia states an object will stay at rest or continue to travel in the same direction at a constant velocity unless acted on by an unbalanced force

Question 29

Newton's second law of motion

Answer 29

F=ma states that the rate of acceleration of a body is proportional to the force applied to it and in the direction in which the force is applied

Question 30

Newton's third law of motion

Answer 30

states that for every action there is an equal and opposite reaction (force)

Question 31

Lever

Answer 31

a lever is a rigid bar that allows the application of either increased force and/or speed

Question 32

Mechanical advantage

Answer 32

formula: force arm/resistance arm mechanical advantage is a measure of how much a lever amplifies force.

Question 33

Static equilibrium

Answer 33

the state in which a body has zero velocity and zero acceleration. A body in equilibrium when the sum of all movements acting on the body are zero

Question 34

Dynamic equilibrium

Answer 34

the state in which a body is in motion with a constant velocity

Question 35

Stability

Answer 35

the degree to which a body resists changing its equilibrium

Question 36

Balance

Answer 36

the ability to control the state of equilibrium

Question 37

Centre of gravity (COG)

Answer 37

is the central point of an object around which all of its weight is evenly distributed and balanced

Question 38

The line of gravity

Answer 38

is an imaginary line that passes through the centre of gravity and continues down into the centre of an object’s base of support

Question 39

The base of support

Answer 39

refers to the area of an object that is in contact with the surface supporting it