In pairs can you CAREFULLY go through the exam. Can you then write in your book the title

5 Things I have learnt from the exam

and then list 5 things you have learnt!

Last lesson

Falling!

Gravity = air resistanceTerminal speed

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 speed.

This velocity is called the terminal speed.

Air resistance

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.

Falling without air resistance?

distance

time

Falling without air resistance?

speed

time

Falling without air resistance?

speed

time

Gradient = acceleration = 9.8 m.s-2

Falling with air resistance?

distance

time

Falling with air resistance?

speed

time

Terminal speed

Today’s lesson

Stopping distances

Stopping distances

The distance a car takes to stop is called the stopping distance.

Two parts

The stopping distance can be thought of in two parts

Stopping distances

Thinking distance is the distance traveled whilst the driver is thinking (related to the driver’s reaction time).

Thinking distance

This is affected by the mental state of the driver (and the speed of the car)

Braking distance

This is the distance traveled by the car once the brakes have been applied.

Braking distance

This affected by the speed and mass of the car

Braking distance

It is also affected by the road conditions

Braking distance

And by the condition of the car’s tyres.

Typical Stopping distances YouTube - Top Gear 13-5: RWD Braking Challenge

YouTube - Think! - Slow Down (Extended) (UK)