Biomechanics

Question 1

What are Newton’s three laws of motion

Answer 1

Inertia
Acceleration
Reaction

Question 2

What is newtons 1st law?

Answer 2

body continues state of rest or constant speed unless acted upon by friction

Question 3

what is newton’s 2nd law?

Answer 3

rate of change of momentum is proportionate to size of force and direction

Question 4

what is newton’s 3rd law?

Answer 4

for every action there is an equal and opposite reaction

Question 5

example of inertia

Answer 5

once a rugby player is running it’s harder to stop them but a smaller person will accelerate quicker

Question 6

example of acceleration

Answer 6

the harder you kick a football the faster it will go

Question 7

example of newton’s 3rd law

Answer 7

if a football hits the cross bar it will bounce back

Question 8

two types of force

Answer 8

internal- produced by contraction of a muscle

external- produced by friction or something

Question 9

what are the functions of force?

Answer 9

cause a resting body to move, change direction, accelerate, decelerate or stop

Question 10

what is centre of mass important for?

Answer 10

stability
wider base of support
line of gravity

Question 11

what should be used for vertical forces?

Answer 11

weight + reaction

Question 12

what should be used for horizontal forces?

Answer 12

friction and air-resistance

Question 13

what affects friction?

Answer 13

roughness of ground
roughness of contact surface
temperature
size of normal reaction

Question 14

what affects air-resistance?

Answer 14

velocity
shape
frontal cross-sectional area
smoothness of surface

Question 15

Force (newtons) =?

Answer 15

mass (kg) x acceleration (m/s/s)

Question 16

Momentum (kgm/s) =?

Answer 16

mass (kg) x velocity (m/s)

Question 17

weight (newtons) =?

Answer 17

mass (kg) x acceleration due to gravity (m/s/s)

Question 18

acceleration (m/s/s) =?

Answer 18

(final-initial velocity) (m/s/s) / time taken (s)

Question 19

what is a lever?

Answer 19

a rigid length of bone that turns about a pivot

if the effort is large enough to overcome the load it will pull the bone (lever) to produce movement

Question 20

third lever system

Answer 20

elbow joint pivot

Question 21

second lever system

Answer 21

ball of foot- plantar flexion- take off jump

Question 22

3rd lever system

Answer 22

extension of the neck- preparing to head a football

Question 23

123

Answer 23

FLE