PE - BiomechanicsPE - Biomechanics

Learning Objectives…Learning Objectives…

To understand Newton's lawsTo understand Newton's lawsTo be able to link Newton’s laws to sporting To be able to link Newton’s laws to sporting

examples.examples.To understand the application of forcesTo understand the application of forces

Newton’s First Law of MotionNewton’s First Law of Motion

Sporting Examples: “ A football will stay on the penalty spot until kicked” “A hockey ball will remain still until hit by the stick” “ A football will roll until slowed by friction or another player” “ A hockey ball will not fall from the air without the

application of gravity”

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

Newton’s First Law of MotionNewton’s First Law of MotionA body continues in a state of rest or uniform velocity

unless acted upon by an external force.

Newton’s First Law of MotionNewton’s First Law of MotionA body continues in a state of rest or uniform velocity

unless acted upon by an external force.

PUSH or PULLS can alter a body (object) in the following ways

•Cause a body to move (as seen in the previous slide)

•Cause a body to accelerate

•Cause a body to decelerate

•Cause a body to change direction

•Cause a body to change shape

Cause a body to accelerate

Sporting example: Sailing boat.

The force that causes the boat to acceleration is the wind.

Forces Can -Forces Can -

Forces Can -Forces Can -

Cause a body to decelerate

Sporting example: Sailing boat.

The force that causes the boat to deceleration is the wind.

Forces Can -Forces Can -

Cause a body to change direction

Sporting example: Tennis

The force that causes the Ball to change direction is the racket impact.

Forces Can -Forces Can -

Cause a body to change shape

Sporting example: Golf

The force that causes the ball to change shape is the impact from the club head.

Ball shape is compressed by the force of the club

head on impact

Newton’s Second Law of MotionNewton’s Second Law of Motion

Sporting Examples: “If you kick a football hard, it will go a long way” “If you kick a football softly it wont go very far” “If you hit a hockey ball to the left, it will go left” “If you hit a hockey ball to the right, it will go right”

When a force acts on an object, the motion experienced by the object is proportional to the size

of the force and in the direction in which it is applied.

Newton’s Third Law of MotionNewton’s Third Law of Motion

Sporting Examples: “If a rugby player pushes to the left with their foot, they

swerve to the right.” “A high jumper needs to push down on the ground to be able

to go up.” A football goalkeeper needs to push to the left with their feet

in order to dive to the right.”

For every action there is an equal and opposite reaction.

ACTIONFORCE

REACTION

FORCE

Action force is the goal keeper pushing down into the floor

Reaction force is the goal keeper lifting into the air in

the opposite direction