To find a pattern you need measurements, not impressions. Write down where it is every second.
pattern Something that happens again and again in the same way.
Step 1: Something to Notice
Watch first. The explanation comes later.
A block is pulled with a steady force and its position is written down every second: 0, 4, 16, 36, 64.
Those are not evenly spaced. What is the rule, and where will it be at 5 seconds?
Step 2: Find Out
Run it to 4 seconds. Work out the gaps. Say what second 5 will be before you look.
Step 1 — Predict
The block moves 4 cm in the first second. How far in the second second?
Choose what you think will happen. You cannot see the experiment until you do — guessing first is what makes it worth watching.
Step 3: So Here Is Why
Now the explanation, after you have seen it happen.
Look at the gaps
The positions themselves look messy. The gaps between them are where the pattern lives.
The gaps grow
With a steady force the gaps get bigger by the same amount each second: 4, 12, 20, 28.
Then you can predict
If each gap is 8 more than the last, the next gap is 36 — so you know where it will be before it gets there.
A pattern lets you predict
If each extra weight makes the trolley go ten centimeters further, you can say what five weights will do before trying it. Predicting and then checking is more useful than only measuring.
A wrong prediction is useful
If the fifth row does not match your prediction, either the pattern was not what you thought or something went wrong in the test. Either way you have learned something you would not have otherwise.
prediction What you think will happen, before it happens.
Step 4: A Common Mistake
Lots of people think
“If a force keeps pulling, the object moves the same distance every second.”
Step 5: Galileo Did Exactly This
The same idea somewhere new.
Four hundred years ago Galileo rolled balls down a ramp and timed them with a water clock. He found the same thing: the distances in each second go 1, 3, 5, 7, 9. It is one of the oldest measured patterns in science, and you have just measured it too.
Step 6: Think It Through
Practice makes it stick.
The Measurements
Problem 1 of 1
A block is at 0, 1, 4, 9, 16 cm after each second. How far will it have gone after 5 seconds?
cm
Read the Pattern
1 of 4
Positions are 0, 4, 16, 36. What is the gap between 16 and 36?
cm
2 of 4
The gaps are 4, 12, 20. What is the next gap?
cm
3 of 4
With a steady force, what happens to the distance covered each second?
4 of 4
Why is a pattern useful?
Step 7: Quick Check
Show what you know.
Question 1 of 1
Positions are 0, 1, 4, 9. Where will it be at 4 seconds?
cm
Step 8: Explain It in Writing
Claim, evidence, then reasoning.
The question
You stopped the run at 4 seconds and said where the block would be at 5. Using the table, write an argument answering the question: does a steady pull move the block the same distance every second?
Evidence you can use
- The table read 4 cm at 1 second, 16 cm at 2 seconds, 36 cm at 3 seconds and 64 cm at 4 seconds.
- The gaps between those rows were 4, then 12, then 20, then 28.
- Every gap was 8 cm bigger than the gap before it.
- I worked out that the next gap would be 36, so I said 100 cm for 5 seconds.
- At 5 seconds the table said 100 cm.
- The pull stayed on 3 and the surface stayed on wood for the whole run.
- Ice is more slippery than wood.
Words to usepatterngapssteadyspeeding uppredictthe same
Fill in all three boxes. The reasoning box is the one that matters most.
What You Found Out
- Measure the position every second and write it down.
- The pattern is in the gaps, not the positions.
- With a steady force the gaps grow by the same amount each second.
- Once you know the pattern you can predict.