Week 1

Question 1

What is biomechanics

Answer 1

Synthesis of biology and mechanics that seeks to

understand and explain human movement

Question 2

Biomechanics is used in the analysis of: name 4

Answer 2

 Sports technique
 Improve performance
 Predict performance
 Monitor rehab
 Assess equipment
 Design equipment
 Postural deficiencies
 Work environments
 Prevent injuries

Question 3

Describes motion

Answer 3

A movement that occurs without force - Kinematics

Question 4

The study of forces that cause motion

Answer 4

Kinetics

Question 5

Two types of Kinetics

Answer 5

Torque and Force

Question 6

Three types of Kinematics

Answer 6

Displacement, Velocity, Acceleration

Question 7

Kinematics and Kinetics can be both Linear and _______

Answer 7

Angular

Question 8

Scalar measurement

Answer 8

A physical quantity that is described by its magnitude

Question 9

Vector measurement

Answer 9

Vector is a measurement that refers to both the magnitude of the unit and the direction of the movement the unit has taken

Question 10

Examples of scalar measurements

Answer 10

Mass, distance, speed, time

Question 11

Examples of vector measurements

Answer 11

Force, displacement, velocity, acceleration

Question 12

Qualitative in reference to biomechanics

Answer 12

Implies that description of motion is done without the use of numbers

Question 13

Quantitative in reference to biomechanics

Answer 13

Implies that description is made with numbers

Question 14

3 types of motion

Answer 14

Linear - translatory motion
Angular - rotation around an axis
General - combination of both linear and angular

Question 15

Rectilinear

Answer 15

Straight line - 100m run

Question 16

Curvilinear

Answer 16

Slight curve to the linear motion - long jump

Question 17

Two types of axis in angular motion

Answer 17

Internal and external axis

Question 18

What plane would elbow flexion be in from the anatomical position

Answer 18

Sagittal plane

Question 19

What plane would hip abduction be in from the anatomical position

Answer 19

Frontal plane

Question 20

Internal rotation of the leg would be in what plane

Answer 20

Transverse plane

Question 21

Linear displacement

Answer 21

Vector - Change in location from the initial to the final position (must contain direction)

Question 22

Linear velocity

Answer 22

Vector - The rate of change in displacement

Question 23

Linear velocity equation

Answer 23

𝑣 =∆ 𝑑 / ∆ 𝑡

∆ = change

Question 24

Linear acceleration

Answer 24

The rate of change in velocity

Question 25

Linear acceleration equation

Answer 25

𝑎 =∆ 𝑣 / ∆ 𝑡

broken down into:

𝑎 = 𝑣f − 𝑣i / 𝑡f − 𝑡i

vf = velocity final
vi = velocity initial
tf = time final
ti = time initial

(∆ = change)

Question 26

What is the average acceleration of a runner who is travelling at a
velocity of 2 m/s forwards at 1 second and at 6 m/s by 7 seconds?

Answer 26

a = 0.66 m/s2 forwards

Question 27

Average velocity

Answer 27

Velocity throughout a given time period

e.g. Velocity of golf club throughout swing

Question 28

Instantaneous velocity

Answer 28

Velocity at a precise point in time (at an instant)

e.g. Velocity of golf club upon impact with ball

Question 29

Instantaneous velocity equation

Answer 29

𝑣𝑖 = 𝑑𝑖+1 − 𝑑𝑖 −1 / 𝑡𝑖+1 − 𝑡𝑖 −1

vi = velocity at an instant (i) in time (measured in m/s)
di + 1 = displacement at frame after instant (measured in m)
di - 1 = displacement at frame before instant (measured in m)
ti + 1 = time at frame after instant (measured in s)
ti - 1 = time at frame before instant (measured in s)

Question 30

Usain bolt’s 100m sprint. 6 frames were captured with his time and displacement.

Calculate the instantaneous velocity of frame 5 with the values of frame 4 (4.85s & 60m) and frame 6 (9.58s & 100m)

Answer 30

8.46 m/s

rounded to two decimal places

Question 31

Instantaneous acceleration equation

Answer 31

𝑎𝑖 = 𝑣𝑖+1 − 𝑣𝑖 −1 / 𝑡𝑖+1 − 𝑡𝑖 −1

Question 32

Does -ve acceleration mean you’re slowing down?

Answer 32

No as you could be accelerating in a negative direction

Question 33

When you are at maximum velocity, what is your acceleration?

Answer 33

zero