Y E A R 8 – F O R C E S

AIR RESISTANCE

AIM & HYPOTHESIS

• AIM: To determine what size parachute will fall the slowest.

• HYPOTHESIS: Write down your hypothesis.

BACKGROUND INFORMATION

• Air resistance is a type of friction between air and another material. This is what makes parachute work. If a person were to skydive without a parachute, they’d push the air molecules out of the way very easily, so the air wouldn’t be able to do much to slow the person down.

• But if the person is attached to a parachute, then the parachute will run into lots of air molecules, and especially if it’s curved to be higher up in the middle, it will be very hard for the air molecules to get out of the way. If they can’t get out of the way, they will slow the parachute (and hence the person) down.

• In this experiment, we will look at how the size of a parachute affects the time it takes to fall.

EQUIPMENT

• Plastic bag• Scissors• String• Rubber stopper• Stopwatch• Ruler

RISK ASSESSMENT

Risk Injury Prevention

Fill out a risk assessment for your experiment

METHOD

1. Cut out a large square from your plastic bag or material about 10x10 cm.

2. Trim the edges so it looks like an octagon (an eight sided shape).

3. Cut a small hole near the edge of each side.

METHOD

4. Attach 8 pieces of string of the same length to each of the holes.

5. Tie the pieces of string to the rubber stopper.

6. Use a chair or find a high spot to drop your parachute and time how long it takes to fall to the ground.

METHOD

7. Repeat experiment step 6, 3 times.

8. Repeat experiment with a 20x20 cm parachute and a 30x30 cm parachute.

RESULTS

Parachute Size Trial 1 (secs)

Trial 2 (secs)

Trial 3 (secs)

Average Time (secs)

1

2

3

DISCUSSION

• How does a parachute work?• Do bigger parachutes work better than smaller

parachutes? Explain why this is the case.

CONCLUSION

Write your conclusion here.