PE: How are skills improved

Newtons Laws of Motion

• Law of Inertia

• Law of acceleration

• Law of action-reaction

Newton's 1st Law of Motion

• law of inertia
• a object will remain at rest or in constant state unless acted upon by an unbalanced external force

Newton's 2nd Law of Motion

• law of acceleration
• a force applied to an object will produce a change in motion in the direction of the applied force (proportion to the size and mass of the object)

Newton's 3rd Law of Motion

• law of action-reaction
• for every action there is an equal but opposite reaction

force

a push or pull acting on another object

moment of inertia

An object's reluctance to rotate

impulse

the product of force and time applied over a period of time

Friction

opposes the motion or an object and occurs when two surfaces come into contact with one another

Inertia

the tendency of a body to resist change in it's state of motion

distance

the length between two points

displacement

the distance between the initial position and the final position

speed

distance/time

velocity

displacement/time

Momentum

momentum = mass x velocity

• the amount of motion an object has and it's resistance to change that motion

conservation of momentum

the total amount of momentum before the collision is eual to the total amount of momentum after the collision

summation of momentum

the sequential and coordinated movement of each body segment to produce max velocity

Torque

a rotational (push or pull force) that makes an object rotate.

Equilibrium

when there is no unbalanced force or torque acting upon it

static

the body or object must not be moving or rotating

dynamic

the state in which the body or an object is moving with a constant velocity

stability

the resistance to disruption of equilibrium

balance

the ability to control the equilibrium

base of support

is bound by the outside edges of the body parts

centre of gravity

the point which the body weight is balanced regardless of the position

line of gravity

the direction in which the gravity acts

levers

a simple machine consisting of a rigid bar that can be made to rotate around an axis in order to exert force on another object

3rd class levers

the force is loated between the axis and the resistance

mechanical advantage

the ratio of the force arm to the resistance arm

projectile motion

refers to the motion that any object or body possess when released into the air