Biomechanics

Question 1

Biomechanical principles

Law of inertia (1st law)

Answer 1

A body will remain in a state of rest or uniform velocity unless acted upon by an external/unbalanced force.

Question 2

Biomechanical principles

What is a sporting example for Newton’s law of inertia (1st law)

Answer 2

A football will remain at rest on a penalty spot until a force is applied from the player’s foot

Question 3

Biomechanical principles

Law of acceleration (2nd law)

Answer 3

The acceleration of a body is proportional to the size of the force applied and takes place in the direction the force is applied. F=ma

Question 4

Biomechanical principles

Law of reaction (3rd law)

Answer 4

Every action has an equal and opposite reaction

Question 5

Biomechanical principles

What is a sporting example for Newton’s law of acceleration (2nd law)

Answer 5

The acceleration of a netball during a pass is proportional to the force from the player’s hands and is in the same direction as the force

Question 6

Biomechanical principles

What is a sporting example for Newton’s law of reaction (3rd law)

Answer 6

When serving, a tennis player pushes downwards on the ground (action force) and the ground pushes upwards on the player (normal reaction force)

Question 7

Biomechanical principles

Weight

(vertical force)

Answer 7

Acts downwards from the centre of mass

Question 8

Biomechanical principles

Reaction

(vertical force)

Answer 8

Acts upwards from the points of contact with the ground, in reaction to all downward forces

Question 9

Biomechanical principles

Friction

(horizontal force)

Answer 9

Opposes the sliding motion of one surface across another

Question 10

Biomechanical principles

Air resistance

(horizontal force)

Answer 10

Acts against the direction of motion, opposing the movement of the body through the air

Question 11

Biomechanical principles

4 factors affection friction

Answer 11

1. Characteristics/roughness of surface1- e.g. sole of footwear
2. Characteristics/roughness of surface2- e.g. playing surface
3. Weight/normal ground reaction force
4. Temperature (e.g. heated tyres increase friction between track and rubber tyres)

Question 12

Biomechanical principles

3 ways to maximise friction

Answer 12

• Increase roughness of either surfaces- e.g. studded boots, dimpled netball
• Increase mass
• Increase temperature- e.g. tyre heaters