2022 Topic Test Biomechanics

Question 1

Name and define the 4 types of frictional force

Answer 1

1. Static Friction: Friction between two objects that are not moving.
2. Sliding Friction: This occurs when two objects slide over each other.
3. Rolling Friction: When one object rolls across another object.
4. Fluid Friction: Friction caused by water or air.

Question 2

What is Newtons 1st Law of Motion

Answer 2

A body continues in a state of rest or state of motion unless acted upon by an external force.

Question 3

Define Inertia

Answer 3

Inertia is the term used to describe the amount of resistance to change in an objects state of motion

Question 4

What is Newtons 2nd Law of Motion

Answer 4

The rate of change of acceleration to a body is proportional to the force applied to it and inversely proportional to the mass of the object”

Essentially, it is Force = Mass x Acceleration

Question 5

Define Momentum

Answer 5

Momentum is a measure of the amount of motion possessed by a moving body and can be expressed mathematically as p=mv

Question 6

Define Impulse

Answer 6

Impulse is the application of force over a period of time to change the momentum of an object.

Question 7

What is Newtons 3rd Law of Motion

Answer 7

For every action, there is an equal and opposite reaction.

Question 8

What 3 factors affect the Coefficient of Restitution

Answer 8

1. Equipment and Materials
2. Temperature of the balls
3. Velocity of the collision

Question 9

What is a concentric force in regards to biomechanics?

Answer 9

Force applied to produce linear motion (knuckleball)

Question 10

What is an eccentric force in regards to biomechanics?

Answer 10

Force applied to produce angular momentum (curveball)

Question 11

Define Torque

Answer 11

Torque is the turning effect created as a result of an eccentric force being applied around a pivot or axis.

Question 12

Define Angular Momentum

Answer 12

The quantity of angular motion possessed by a rotating body and is expressed mathematically as;

Angular momentum = angular velocity * moment of inertia

Question 13

What is the lever rule?

Answer 13

FLE - 123

Question 14

Name and describe the two factors that affect fluid resistance

Answer 14

1. Density: The more dense the fluid, the more disturbed the fluid becomes and hence the greater the resistance
2. Viscosity: The more viscous the fluid (internal resistance of a fluid to flow), the more disturbed the fluid becomes and hence the greater the resistance

Question 15

Name and describe the three types of drag

Answer 15

1. Surface Drag: Friction produced between fluid and surface of a moving object
2. Form Drag: Resistance created by pressure differential between front and back of an object
   moving through a fluid
3. Wave Drag: Resistance formed by creation of waves at the point where air and water
   interact.

Question 16

What are the six factors that will affect drag

Answer 16

1. Drag Coefficient
2. Cross Sectional Area
3. Speed
4. Surface Roughness
5. Mass
6. Shape

Question 17

Define Bernoulli’s Principle

Answer 17

As the velocity of a fluid increases, the pressure the fluid exerts on an object decreases. Velocity is inversely proportional to pressure.