Biomechanics part 1

Question 1

Define Newton’s 1st law of motion (linear)?

Answer 1

NL1 = Inertia: A body continues in a state of rest or constant velocity unless acted upon by an external force.

Question 2

M________ of I_______ is the resistance of a body to change its rotation?

Answer 2

Moment of Inertia

Question 3

Name the force that opposes the motion of two surfaces in contact (anti-slipping force)?

Answer 3

Friction (N)

Question 4

A push or pull that alters the state of motion/movement of a body is known as a f____ and is measured in N_______

Answer 4

Force, Newton’s

Question 5

Ice skating pirouette: during mid flight moment of inertia is ____ and angular velocity is ____ because m___ is distributed close to the l____________ axis of rotation

Answer 5

low, high, mass, longitudinal

Question 6

A_________ M__________ is the quantity of rotation possessed

Answer 6

Angular Momentum

Question 7

Describe angular velocity

Answer 7

Rate of change in rotation (rate of spin)

Question 8

Define Newton’s 2nd law of motion (linear)?

Answer 8

NL2 = Acceleration: A body’s change of momentum (velocity) is proportional to the size of the force applied and it acts in the same direction as the force applied.

Question 9

Name the force that opposes motion through the air?

Answer 9

Air resistance (N)

Question 10

A force applied directly through the centre of mass resulting in linear motion is called a d______ force

Answer 10

Direct

Question 11

Define momentum.

Answer 11

The quantity of motion/movement possessed by a moving body

Question 12

A force applied outside the centre of mass resulting in angular motion (rotation) is called an e________ force

Answer 12

Eccentric

Question 13

Name the 4 factors affecting air resistance/drag (4S’s)?

Answer 13

1. Size of frontal cross sectional area
2. Speed
3. Surface characteristics
4. Shape/Streamlining

Question 14

When moment of inertia is high, angular velocity is ___

Answer 14

low

Question 15

Newton’s law of angular motion states a rotating body will continue to turn abouts its a___ of r________ with constant a_______ m___________unless acted upon by an eccentic force

Answer 15

axis of rotation, angular momentum

Question 16

Angular motion results from an ________ force applied outside the COM

Answer 16

Eccentric

Question 17

What is the effect that base of support has on stability?

Answer 17

Increased base of support = increase stability

Question 18

Name the force that is the equal and opposite force exerted by a body in response to the action force placed upon it e.g. sprinter pushes foot against the starting blocks-starting blocks exert an equal and opposite force back

Answer 18

Reaction (measured in Newton’s)

Question 19

Describe a sporting example of Newton’s third law:

Answer 19

Golf club exerts forward force on the ball. Ball exerts an equal and opposite force on the ball.

Question 20

The force that opposes motion/movement through the air is called?

Answer 20

Air resistance

Question 21

Name the force that is the gravitational pull of the earth on a body?

Answer 21

Weight (N)

Question 22

What is angular velocity?

Answer 22

Rate of change in rotation (angular displacement)

Question 23

Cyclists use lycra to improve ?

Answer 23

Surface characteristics-lycra suits reduce air resistance

Question 24

Name the 4 factors affecting stability?

Answer 24

1. Mass (greater the mass greater the stability e.g. sumo wrestler)
2. Height of Centre of Mass (lower CoM = greater stability)
3. Size of base of support (more points of contact/wider base = greater stability)
4. Line of gravity/CoM (more central the line of gravity/CoM to base of support = greater stability)

Question 26

When moment of inertia = low, angular velocity=?

Answer 26

High

Question 27

Ice skating pirouette during landing phase, moment of inertia is ___ and angular velocity is ___

Answer 27

high , low

Question 28

Name the 4 factors affecting friction (4R's)?

Answer 28

1. Roughness of contact surface, 2. Roughness of ground surface, 3. Reaction force 4. tempeRature

Question 29

The force that opposed the motion of 2 surfaces in contact (anti slipping force) is known as f_______ and is measured in N_______

Answer 29

Friction & Newton’s

Question 30

Whats's the relationship between line of gravity and stability?

Answer 30

More central line of gravity = increase stability

Question 31

What happens to Centre Of Mass during the Fosbury Flop in high jump? Think about take-off and flight

Answer 31

Take off = arms raised COM higher but within body | Flight = COM located outside the body, under the bar

Question 32

Which of Newton's laws states that a body continues in a state of rest or constant velocity unless acted on by an external force?

Answer 32

Newton's first law- law of inertia

Question 33

Name the memory hook for the 3 axes of rotation? Give a sporting example for each axis.

Answer 33

Lollies, Taste, Fruity L-Longitudinal (Longest = top to bottom-a trampolinist performing a full twist) T-Transverse (Table football = side to side-a front somersault) F-Fruity (Front to back-a cartwheel)

Question 34

The gravitational pull of the earth on a body is known as w______ and is measured in N_______

Answer 34

Weight & Newton’s

Question 35

How do you calculate force according to newton's second law?

Answer 35

Force= Mass x acceleration

Question 35

Describe moment of inertia

Answer 35

Resistance of a body to change its rotation

Question 36

The memory hook for planes and axis is?

Answer 36

Tuna, Smells, Fishy (Planes) | Lollies, Taste, Fruity (Axis)

Question 37

Movement of a body in a straight or curved line, where all body parts move the same distance, in the same direction over the same time is called ________ motion.

Answer 37

Linear

Question 38

What is Centre of Mass?

Answer 38

Point at which weight appears to act/ where an object is balanced in all directions.

Question 40

The force that opposes motion/movement through water is called d____ and is measured in N_______

Answer 40

Drag, Newton’s

Question 41

State Newton's Third Law of motion (linear)?

Answer 41

NL3 Reaction: For every action there is an equal and opposite reaction

Question 42

Name the 2 factors affecting your moment of inertia (resistance to rotation)

Answer 42

1. Mass | 2. Distribution of mass from axis of rotation

Question 43

The rate of change of velocity (speed) is known as a____________

Answer 43

Acceleration (m/s/s)

Question 44

The sum of all forces acting on a body is called n__ force. This can either be balanced (zero) or unbalanced (+ or -)

Answer 44

Net

Question 45

Spin (rotation) is created by an e________ force applied outside the centre of mass (CoM)

Answer 45

eccentric

Question 45

Which of Newton’s Laws refers to a body's change in momentum (acceleration) is proportional to the size and direction of the force applied.

Answer 45

Newton's second law- law of acceleration