Linear motion (P2) Flashcards
What is linear motion?
Motion in a straight or curved line, with all body parts moving the same distance at the same speed in the same direction.
What is Newton’s first law of motion?
Every body continues in its state of rest or motion in a straight line, unless compelled to change that by external forces exerted upon it
What is Newton’s second law of motion?
The magnitude and direction of the force determines the magnitude and direction of the acceleration.
What is Newton’s third law of motion?
For every action (force), there is an equal and opposite reaction force
What is an example of Newton’s first law of motion?
High jumper travels horizontally until their quadriceps contract to compel them upwards.
What is an example of Newton’s second law of motion?
To provide the the acceleration of a 100m sprint, the sprinter has to apply a large internal force from contraction of muscles
What is an example of Newton’s third law of motion?
Sprinter pushes against the blocks and the blocks pushes against the sprinter.
What is ground reaction force?
The equal and opposite force exerted on a performer who applies a muscular force on the ground.
What is the centre of mass?
The point of concentration of mass, the point of balance of the body.
What is the line of gravity?
The line extending vertically downwards from the centre of mass.
What factors affect stability?
. The height of the centre of mass
. Position of the line of gravity
. Area of the support base
. Mass of the performer
How does the height of the centre of mass affect stability?
Lowering the centre of mass increases stability
How does the position of the line of gravity affect stability?
Should be central over the base of support to increase stability.
How does the area of the support base affect stability?
The more contact points, the larger the base of support and the more stability.
How does the mass of the performer affect stability?
Often the greater the mass, the greater the stability because of increase inertia.
