5.1 Biomechanical principles Flashcards
Explain the term ‘Biomechanical principles’
Biomechanical principles is the understanding of how movements and forces cam be applied to performance in sport
Explain Newtons law of linear motion
Linear motion is motion in a straight or curved lined, with all body parts moving the same distance at the same speed in the same direction.
Summary: all body parts in motion in straight/curved line, at same distance, speed and direction.
Give a sporting example of Newtons law of linear motion
A 100 metre athlete will travel with linear motion in a straight line during a race. A 200 metre athlete will travel with the linear motion in a curved lined when running the bend.
Identify and explain Newtons first law
- Law of Inertia
“Every ‘body’ continues in its state of rest or motion in a straight line, unless compelled to change that state by external forces exerted upon it”
Summary: an external force is required to change the state of motion. An object will remain in a state of constant velocity (rest or motion in straight line) until compelled to change by an external force
Give a sporting example of Newtons first law
If a body changes it state of motion, it starts, stops, accelerates, decelerates or changes direction. For example, in high jump, the athlete runs horizontally towards the bar and then changes state of motion at take off when they travel vertically to clear the bar.
Identify and explain Newtons second law
- Law of acceleration
“The rate of momentum of a ‘body’ is proportional to
- the force causing it
and
- the change that takes place in the direction in which the force acts”.
Summary: magnitude (size) and direction of the force applied to a body determines the magnitude and direction of the acceleration given to a body. The rate of acceleration is proportional to the force causing it to change.
Define the term ‘magnitude’
size
Identify the equation supporting Newtons second law
Law of acceleration:
Force = Mass x Acceleration (F=ma)
Give a sporting example of Newtons second law
Law of acceleration is portrayed when batting in cricket as the more force applied when swinging the bat, the further the ball is going to travel.
Identify and explain Newtons third law
- Law of action/reaction
“To every action, there is an equal and opposite reaction”
Summary: this law describes what happens when two bodies exert forces on on another - action and reaction are equal.
Give a sporting example of Newtons third law
At a sprint start, the athlete pushes back on the blocks (action) and the blocks push forward on the athlete (reaction) - providing forward acceleration on the athlete
During a race, a swimmer has to dive off the starting blocks as quickly as possible. Using Newtons first and second laws of motion, explain how the swimmer dives off the starting blocks
Law of inertia on the swimmer: the swimmer will remain in the motion of rest until the starting gun is heard and they apply force against the blocks to start a dive.
Law of acceleration: the rate of acceleration applied by the swimmer to dive off the blocks is proportional to the force causing it to change.
Explain what is meant by GFR and identify which one of Newtons law suggest it. Give an example to support your answer
Ground Force Reaction - Law or action/reaction (3)
GFR is the force exerted by the ground on a body in contact with it.
For example: In high jump, the more force that is pushed into the floor the more height they’re going to generate to jump up.
Explain what a scalar quantity is
Scalar quantity: measurement that is described in terms of magnitude (size) NOT DIRECTION (it is not taken into account)
Identify the two scalar quantities used in linear motion
Speed
Distance
