1. Air resistance

2. Objects moving through the air experience a type of friction called AIR RESISTANCE Air resistance means that some falling objects can reach a constant speed before they hit the ground It is caused by air particles hitting moving objects

3. Testing air resistance You are going to drop some cones and time how long they take to reach the ground. You will have 4 cones Small paper cone Large paper cone Small card cone Large card cone

4. Different tests You are going to compare pairs of cones You can only change one thing at once Example: compare the small paper cone and the large paper cone Is comparing the large card cone & the small paper cone a good choice?

5. Timing & recording Drop each cone from the same height Use the stopwatch to time the fall Round each time to one decimal place. E.g. if the stopwatch says 3.14 seconds, write down 3.1 seconds but record 3.15 seconds as 3.2 seconds

6. Results tables 1 st cone2 nd cone Time 1 in seconds Time 2 in seconds Time 3 in seconds Average time in seconds

7. Conclusions The bigger the cone the longer it takes to fall Making the cone larger, makes the air resistance bigger The card cones fall faster than the paper cones. Air resistance has more effect if the object is lighter.

8. Questions Think of a sentence about each of these pictures using the idea of air resistance.