You can describe things as long or heavy. Now compare two things directly.
Key idea
To compare lengths, line up the ends. To compare weights, use a balance, or hold one thing in each hand.
Why it works
When the starting ends match, the one that reaches farther is longer. On a balance, the heavier side pulls down.
Worked example: Heavier or lighter?
Which is heavier, a book or a feather?
- Put one on each side of a balance.
- The book side goes down.
- The book is heavier. The feather is lighter.
Answer: The book
Common mistake
Comparing without lining up the ends, so the one that sticks out looks longer. It may just start later! Slide them so the ends match before you decide.
For grown-ups: Compare shoes, spoons and pencils by lining them up at one end. Hold two fruits and decide which is heavier.