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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 resistance Terminal speed.
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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 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 gravity
gravity Falling without air resistance 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 Gradient = acceleration = 9.8 m.s-2 time
Falling with air resistance? distance time
Falling with air resistance? Terminal speed speed time
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 ChallengeYouTube - Think! - Slow Down (Extended) (UK)