Paper1 Biomechanics: Linear Motion, Angular Motion, Fluid Mechanics and Projectile Motion

Question 1

linear motion

Answer 1

results from a direct force applied to the centre of mass

Question 2

distance

Answer 2

total length from start to finish measured in m

Question 3

displacement

Answer 3

shortest straight line from start to finish measured in m

Question 4

speed

Answer 4

rate of change of distance
distance/time taken
measured in m/s

Question 5

velocity

Answer 5

rate of change of displacement
displacement/time taken
measured in m/s

Question 6

acceleration/deceleration

Answer 6

rate of change in velocity
final velocity-initial velocity/time taken
measured in m/s/s

Question 7

angular motion

Answer 7

results from an eccentric force outside of the CofM

Question 8

3 axis of rotation

Answer 8

longitudinal
transverse
frontal

Question 9

longitudinal axis of rotation

Answer 9

from the top to the bottom of the body e.g., trampolinist performs a twist turn

Question 10

transverse axis of rotation

Answer 10

from side to side of the body e.g., a front sommersault

Question 11

frontal axis of rotation

Answer 11

from the front to the back of the body e.g., a cartwheel

Question 12

moment of inertia

Answer 12

resistance of a body to change its state of rotation
sum(mass x distribution of mass from the axis of rotation)
kgm2

Question 13

angular velocity

Answer 13

rate of change of angular displacement or rate of rotation
angular displacement/time taken
radians/sec (rad/s)

Question 14

angular momentum

Answer 14

quantity of angular motion possessed by a body
moment of inertia x angular velocity
kgm2/s

Question 15

factors affecting size of moment of inertia

Answer 15

mass
distribution of mass

Question 16

how mass affects MI

Answer 16

greater the mass the greater the MI

Question 17

how distribution of mass affects MI

Answer 17

the further the mass from the axis of rotation the higher the MI

Question 18

MI effect on angular motion

Answer 18

as MI increases, resistance to rotation increases

Question 19

conservation of angular momentum

Answer 19

angular momentum remains constant until an external eccentric force is applied

Question 20

fluid mechanics

Answer 20

study of forces acting on a body through the air or in water

Question 21

factors affecting air resistance and drag

Answer 21

velocity
frontal cross-sectional area
streamlining and shape
surface characteristics

Question 22

how velocity affects air resistance/drag

Answer 22

the greater the velocity, the greater the air resistance/drag

Question 23

how frontal cross sectional area affect air resistance/drag

Answer 23

the larger the area the larger the air resistance/drag

Question 24

how streamlining and shape affects air resistance/drag

Answer 24

the more streamlined an object is the less air resistance/drag

Question 25

how surface characteristics affect air resistance/drag

Answer 25

more smooth a surface is the less air resistance/drag

Question 26

projectile motion

Answer 26

movement of a body through the air following a curved flight path

Question 27

factors affecting the horizontal distance travelled by a projectile

Answer 27

speed of release
angle of release
height of release
aerodynamic factors

Question 28

how speed of release affects distance travelled

Answer 28

the greater the speed of release the further it will travel

Question 29

how angle of release affects distance travelled

Answer 29

45 degrees is the optimal angle of release

Question 30

how height of release affects distance traveled

Answer 30

if the release height is higher than the landing height optimal angle of release is <45 degrees
if release height is lower then the landing height, optimal angle of release is >45 degrees

Question 31

how aerodynamic factors affect distance travelled

Answer 31

bernouli and magnus

Question 32

parabolic flight path

Answer 32

weight>air resistance produces parabolic projectile
eg. shot put

Question 33

non-parabolic flight path

Answer 33

if air resistance is the dominant force over weight the projectile follows a non-parabolic flight path e.g., a badminton shuttle

Question 34

bernoulli principle

Answer 34

creation of an additional lift force on a projectile from the conclusion that the higher the velocity of air flow, the lower the surrounding pressure
as velocity increases pressure decreases
as fluids move from high to low pressure, a pressure gradient forms creating an additional lift force

Question 35

aerofoil shape

Answer 35

curved upper surface forcing air flow to travel a further distance and at a higher velocity
flat underneath - air travels a shorter distance at a lower velocity

Question 36

downward lift force

Answer 36

brenoullis principle works in the opposite direction if the aerofoil shape is inverted
this is important for formula 1

Question 37

topspin

Answer 37

eccentric force applied above C of M
projectile spins downwards

Question 38

backspin

Answer 38

eccentric force applied below C of M
projectile spins upwards

Question 39

sidespin hook

Answer 39

eccentric force applied right of C of M
projectile spins left

Question 40

sidespin slice

Answer 40

eccentric force applied left of C of M

Question 41

magnus force

Answer 41

created from a pressure gradient on opposing surfaces of a spinning body