Presentation is loading. Please wait.

Presentation is loading. Please wait.

What effects how quickly a car stops? Aims: To understand that stopping distances are related to friction and speed To understand what speed is and how.

Similar presentations


Presentation on theme: "What effects how quickly a car stops? Aims: To understand that stopping distances are related to friction and speed To understand what speed is and how."— Presentation transcript:

1 What effects how quickly a car stops? Aims: To understand that stopping distances are related to friction and speed To understand what speed is and how it is measured To be able to interpret distance/time graphs

2 Speed and stopping Speed tells you how far you go in a certain time The speed of a car affects how long it takes to stop The faster you are going, the longer it takes to stop Thinking time = the distance you travel whilst THINKING about stopping Braking distance = the distance you travel once you start to BRAKE

3 Stopping a car… Braking distance Too much alcohol Thinking distance Tiredness Too many drugs Wet roads Driving too fast Tyres/brakes worn out Icy roads Poor visibility

4 Distance-time graphs ) Diagonal line downwards = 3) Steeper diagonal line = 1)Diagonal line = 2) Horizontal line = Distance (metres) Time/s

5 )How far had the object gone after 20 seconds? 2)How far had the object gone after 60 seconds? 3)When is the object standing still? 4)When was the object travelling the fastest? Distance (metres) Time/s

6 Activity 1 : Complete the worksheet (10 minutes)

7 Activity 2 How could we compare the speeds of a car on two different surfaces (The pink box on page 23 spotlight 8 may help)

8 © Boardworks Ltd 2003 Use this equation: SPEED = distance time Speed is measured in many different units, e.g. m/s, km/h, km/s, miles per hour. The units of distance and time used will give the units to be used for speed. d sxt Formula triangle Formula triangle for measuring speed

9 © Boardworks Ltd 2003 Formula triangle

10 © Boardworks Ltd 2003 A boy travels from his home to the cinema, a distance of 10 km in 1 hour. Calculate his speed in km/h. Examples Speed in km/h = d sxt Cover the quantity you want to calculate - s (speed) d (distance in km) t (time in h) 10 km 1 h = = 10 km/h

11 Work out the speed of the two cars which is the fastest?

12 Complete the table on page 22 spotlight 8 then complete questions 1 to 5 on page 23.

13 1.How long did the journey take? 2.What was the total distance covered? 3.What was the average speed for the journey? 4.What was the average speed for the first 20 minutes and the last 20 minutes of the journey? Write a short story about this journey. What is happening in each 10 minute segment? (Finish for homework)


Download ppt "What effects how quickly a car stops? Aims: To understand that stopping distances are related to friction and speed To understand what speed is and how."

Similar presentations


Ads by Google