A good plan starts with a question that can be tested, such as 'Does the area of a parachute affect how long it takes to fall?' Next, name the variables: change the canopy area, measure the fall time, and keep the drop height, the mass and the string length the same.
Then list the equipment and write the method as numbered steps so someone else could repeat it exactly. Decide how many results to take and whether to repeat each one. Finally, think about safety: standing on chairs to drop parachutes needs an adult to hold the chair.
Worked example
Write one control variable for a parachute investigation and explain why.
- Keep the drop height the same.
- A higher drop would give a longer fall time anyway.
Answer:Keeping it the same means only the canopy area affects the result.
Key words
- method
- the steps of an investigation
- equipment
- the things you need
- question
- what the investigation tries to find out
- safety
- keeping people from harm
Practise this
New questions every time.
NGSS-referenced: 5-PS1-3