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Can you read what Mr

Porter has written inyour books?

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Falling!

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Force of gravity means the dog accelerates

gravity

To start, the dog is falling slowly (it has not

had time to speed up).

There is really only one force acting on the

dog, the force of gravity.

The dog falls faster (accelerates) due to thisforce.

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Gravity is still bigger than air resistance

gravity

As the dog falls faster, another force

becomes biggerair resistance.

The force of gravity on the dog of course

stays the same

The force of gravity is still biggerthan the airresistance, so the dog continues to

accelerate (get faster)

Air resistance

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Gravity = air resistance

Terminal velocity

gravity

As the dog falls faster and air resistance

increases, eventually the air resistance

becomes as big as (equal to) the force of

gravity.

The dog stops getting faster (accelerating)

and falls at constant velocity.

This velocity is called the terminal velocity.

Air resistance

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Terminal Speed

The dog will continue to fall at constant speed

(called the terminal speed) until.

gravity

Air resistance

air resistance = gravity

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Terminal Speed

gravity

Air resistance

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Oooooops!

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That definitely was

terminal!

YouTube - Moonraker Pre

Credits

http://www.youtube.com/watch?v=G45QJo2_S-I&feature=relatedhttp://www.youtube.com/watch?v=G45QJo2_S-I&feature=relatedhttp://www.youtube.com/watch?v=G45QJo2_S-I&feature=relatedhttp://www.youtube.com/watch?v=G45QJo2_S-I&feature=relatedhttp://www.youtube.com/watch?v=G45QJo2_S-I&feature=relatedhttp://www.youtube.com/watch?v=G45QJo2_S-I&feature=relatedhttp://www.youtube.com/watch?v=G45QJo2_S-I&feature=related

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Can you stick the sheet

in?

YouTube - Moonraker Pre

Credits

http://www.youtube.com/watch?v=G45QJo2_S-I&feature=relatedhttp://www.youtube.com/watch?v=G45QJo2_S-I&feature=relatedhttp://www.youtube.com/watch?v=G45QJo2_S-I&feature=relatedhttp://www.youtube.com/watch?v=G45QJo2_S-I&feature=relatedhttp://www.youtube.com/watch?v=G45QJo2_S-I&feature=relatedhttp://www.youtube.com/watch?v=G45QJo2_S-I&feature=relatedhttp://www.youtube.com/watch?v=G45QJo2_S-I&feature=related

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Which has the lowest

terminal velocity?Shuttlecock

Table tennis ball

Practice golf ballRolled up ball of A4 paper

Design a results table FIRST!

Lets try a

quick

investigation

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Falling without air resistance

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Falling without air resistance

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Falling without air resistance

gravity

This time there is only one force acting in the

ball - gravity

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Falling without air resistance

gravity

The ball falls faster.

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Falling without air resistance

gravity

The ball falls faster and faster.

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Falling without air resistance

gravity

The ball falls faster and faster and faster.

It gets faster by 10 m/s every second (10 m/s2)

This number is called g, the acceleration due

to gravity.

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Falling without air resistance

gravity

Without air resistance objects fall

faster and faster and faster.

They get faster by 10 m/s every

second (10 m/s2)

This number is called g, the

acceleration due to gravity.

Can you copy the

words please?

Where

did I

come

from?

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Which falls fastest?

Big ball bearingSmall ball bearing

Humungus ball bearing

Design a results table FIRST!

Lets try a

quick

investigation

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Falling without air resistance?

distance

time

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Falling without air resistance?

distance

time

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Falling without air resistance?

speed

time

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Falling without air resistance?

speed

time

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Falling without air resistance?

speed

time

Gradient = acceleration = 9.8 m.s-2

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Falling withair resistance?

distance

time

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Falling with air resistance?

distance

time

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Falling with air resistance?

speed

time

Terminal speed

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Falling with air resistance?

speed

time