W1 & 2 - Angular kinematics

Question 1

Define angular distance

Answer 1

Total angular distance travelled

Question 2

Define angular displacement

Answer 2

Change in angle = difference between initial and final positions units.

Question 3

How is angular velocity calculated

Answer 3

Change in angle / change in time

Question 4

How is angular acceleration calculated

Answer 4

Change in angular velocity / change in time

Question 5

Define absolute angle

Answer 5

Angle defined relative to a line in space

Question 6

Define relative angle

Answer 6

Angle between 2 segments

Question 7

How do you calculate 1 radian?

Answer 7

360 / 2 x pi

Question 8

What is used to calculate angular velocity?

Answer 8

First central difference method

Question 9

How many degrees are in 1 radian?

Answer 9

57.3

Question 10

What is the polarity of a vector

Answer 10

Direction of rotation of an angular motion

Question 11

How is the polarity of vector determined?

Answer 11

Right hand rule

Question 12

What did Winter determine?

Answer 12

That the ankle, knee + hip angles can be defined using the absolute angles of:

Foot
Leg
Thigh
Pelvis

Question 13

What are the ways in which angles can be measured

Answer 13

Radians

Revolutions

Degrees

Radians must be the one used if there are further calculations

Question 14

Define tangeal velocity

Answer 14

Linear velocity of distal end of a rotating segment.

Question 15

For absolute angles, where is the value located if the x + y values are both negative

Answer 15

3rd quadrant

Question 16

For absolute angles, where is the value located if there’s only negative y value

Answer 16

4th quadrant

Question 17

What do you do to an absolute angle if it’s in the 3rd quadrant?

Answer 17

Add 180 degrees

Question 18

What do you do if the absolute angle value is in the 4th quadrant?

Answer 18

Add 360 degrees

Question 19

What would an absolute angle of -3.83 indicate at the ankle joint?

Answer 19

Ankle is in plantarflexion at touchdown

Question 20

Pronation, neutral or supination for a negative rear foot angle?

Answer 20

Pronation

Question 21

Pronation, neutral or supination for a 0 rear foot angle?

Answer 21

Neutral

Question 22

Pronation, neutral or supination for a positive rear foot angle?

Answer 22

Supination

Question 23

Calcaneal inversión, eversión or neutral for positive rear foot angle?

Answer 23

Calcaneal inversión

Question 24

Calcaneal inversión, eversión or neutral for negative rear foot angle?

Answer 24

Calcaneal eversión

Question 25

What else are relative angles known as?

Answer 25

Joint angles Inter segmental angles

Question 26

During typical running gait the highest ankle dorsi flexion at the joint occurs during: a. footstrike b. initial support c. midstance d. toe-off

Answer 26

highest ankle dorsi flexion = mid stance

Question 27

During footstrike at what angle is the knee flexed during normal running gait?

Answer 27

10 degrees

Question 28

Which of the following assumptions are made when analysing sagittal plane lower limb motion during running: (a) the limbs of the body act as rigid links, (b) all movement is in the sagittal plane, (c) there is three-dimensional movement, (d) skin markers represent joint locations.

Answer 28

a, b + d

Question 29

Dixon and Kerwin (1999) found that heel lift devices reduced ankle dorsi-flexion while having no significant influence on knee joint motion. What did they conclude regarding Achilles tendon strain?

Answer 29

That Achilles tendon strain was reduced when using heel lift devices

Question 30

The reliability of joint angle calculations can be optimised by:

Answer 30

By applying joint markers and using the same person to perform all digitising

Question 31

What may provide insight into injury patterns?

Answer 31

Velocity of heal at foot strike

Question 32

Placement of marker issues at the hip

Answer 32

Superior border of the greater trochanter is difficult to locate on an ind. w/ a lot of subcutaneous fat

Question 33

Placement of marker issues on the shoulder

Answer 33

Any marker on the shoulder girdle is likely to give erroneous data due to shoulder being one of the most mobile joints.

Question 34

What is the best method to determine cycle landmarks i.e foot strike + toe-off for overground running?

Answer 34

By measuring GRF w/ the motion + using vertical force value = NOT possible on treadmill