Biomechanical Principles, Levers And Use Of Technology✅

Question 2

What is Newton’s first law (definition)

Answer 2

Law of inertia: a body continues in a state or rest or uniform velocity unless acted upon by an external or unbalanced force

Question 3

What is Newton’s second law (definition)

Answer 3

Law of acceleration: a body’s rate of change of momentum is proportional to the size of the force applied and acts in the same direction as the force applied

Question 4

What is Newton’s third law (definition)

Answer 4

Law of reaction: for every action there is an equal and opposite reaction

Question 5

Give an application for Newton’s first law

Answer 5

Law of inertia: golf ball remains still unless force applied by a golf club makes it move, or golf ball continue to move at constant velocity unless a force acts on it to slow it down (eg wind resistance)

Question 6

Give an application for Newton’s second law

Answer 6

Law of acceleration: golf ball struck by golf club, the rage of change of momentum (or velocity) of ball is proportional to size of force applied to it by club. The bigger the forge the greater the acceleration

Question 7

Give an application of Newton’s third law

Answer 7

Law of reaction: if a tennis plays hits a ball, the racquet exerts a force on the ball and the ball exerts an equal and opposite force on the racquet, the racquet exerts the action force and the ball exerts the reaction force

Question 8

What is the definition and equation for velocity

Answer 8

M/s
Rate of change of displacement (shortest straight line route between start and finish)
Velocity= displacement/time taken

Question 9

What is the definition of momentum and the equation

Answer 9

kgm/s
Quantity of motion possessed by a moving body
Momentum=mass X velocity

Question 10

What is the definition and equation for acceleration

Answer 10

M/s/s
Rate of change in velocity
Acceleration= (final velocity-initial velocity)/ time taken

Question 12

What is the definition and equation for force

Answer 12

N
A push or a pull that alters the state of motion of a body
Force= mass X acceleration

Question 13

What are internal and external forces

Answer 13

Internal: generated by skeletal muscles

External: comes from outside the body

Question 14

What 5 effects can force have

Answer 14

Create motion
Accelerate a body
Decelerate a body
Change the direction of a body
Change the shape of a body

Question 15

If net force is 0 what happens, if a net force is present what happens

Answer 15

No change in motion as forces are balanced

Change in motion as forces are unbalanced, occurs when 2 forces are unequal in size and opposite in direction

Question 16

What are the vertical and horizontal forces in external forces

Answer 16

Vertical: weight (gravitational pull that earth exerts on a body) and reaction (equal and opposite force placed upon it)

Horizontal: friction (force that opposes the motion of two surfaces in contact) and air resistance (force that opposes motion through the air)

Question 18

What factors affect friction, give example for each one

Answer 18

Roughness of ground surface (athletes run on rough, rubberized tracks)

Roughness of contact surface (athletes wear spiked shoes)

Temperature (F1 drivers warm up tires)

Size of normal reaction (shot putters have high mass, Newton’s third law, allowing grater friction in the throwing circle and preventing over-rotation

Question 19

What factors affect air resistance, give example for each one

Answer 19

Velocity (greater the velocity of a cyclist, the greater the force of air resistance opposing their motion)

Shape, (most cyclists wear helmet with tear drop or aero foil shape, streamline)

Frontal cross-sectional area, (the low crouched position of a downhill skier reduces air resistance)

Smoothness of surface, (increased smoothness from Lycra suits reduces air resistance)

Question 20

How do you draw a free body diagram

Answer 20

W (from CoM) and R (from point of contact) as vertical forces

F (from point of contact) and AR (from CoM) as horizontal forces

Include direction of motion and correct length of arrows to show relative proportions

Question 21

What is the centre of mass

Answer 21

The point at which an object or a body is balanced in all directions; the point at which weight appears to act

Question 22

What factors affect stability

Answer 22

Mass of body: greater the mass, the greater the inertia

Height of centre of mass: the lower the CoM, the greater the stability

Base of support: the greater the size of the base of support, the greater the stability, this can be increased by more points of contact

Line of gravity: the more central the line of gravity to the base of support, the greater the stability

Question 23

When would you want to maximize and minimize stability for a sprinter

Answer 23

Maximize stability in the blocks (low CoM, large base of support, line of gravity in line with CoM, low height of CoM)

Minimize stability to aid performance (chest lifts, raising CoM; hands come off track, reducing base and contacts of support; line of gravity falls infront of body, causing the body to fall forwards)

Question 24

What is a first class lever, give an example

Answer 24

Fulcrum is in the middle

Extension of neck when preparing to head a football (E-F-L)

Question 25

What is a second class lever, give an example

Answer 25

Load is in the middle Extension of Ball of the foot in the take-off phase of a high jump (E-L-F)

Question 26

What is a third class lever, give an example

Answer 26

Effort is in the middle Flexion of the elbow during a biceps curl (L-E-F)

Question 27

How to maximize efficiency of a lever

Answer 27

The smaller the distance of the effort or load from the fulcrum the less significant the effort or load becomes Longer levers generate greater forces as the load as load arm becomes longer and therefore can give greater acceleration to projectiles

Question 28

Give an example of a mechanical advantage

Answer 28

Second class lever has advantage to move large load with small effort, such as at ball of foot to vertically accelerate an atheletes whole weight easily

Question 29

Give an example of a mechanical disadvantage

Answer 29

Third class lever has disadvantage, requiring large effort to move relatively small load eg flexion of elbow in upwards phase of bicep curl

Question 30

Give definition and use of limb kinematics and optimizing performance

Answer 30

Study of movement in relation to time and space 3D or optical motion analysis records an athlete performing a sporting action, allowing evaluation of efficiency of movement Data producer can be used by coaches to improve performance/specific techniques of athletes

Question 31

Give definition, use and how to optimize performance for force plates

Answer 31

Ground reaction forces are measured in laboratory conditions using force plates Athletes balance, run and jump on force plates, which access sixe and direction or force, acceleration rates, work and power output Used for sports biomechanics, physical therapy, balance rehabilitation, gait analysis

Question 32

Give definition, use and how to optimize performance for wind tunnels

Answer 32

Steel frame building containing wide fans, where artificial wind is produced Technology used to develop DRS, objects such as cycle helmet L’s and F1 cars can be tested for aerodynamic efficiency Engineers study flow of air around an object, aim to improve flow of air around an object, making more streamline, increasing lift or reducing drag