Even though iron feels heavier to most people because it’s denser and takes up less space, 1 kg of cotton and 1 kg of iron both weigh exactly the same — one kilogram.
The trick in this question lies in our perception — we imagine iron as “heavier” because it’s solid and compact, while cotton is soft and fluffy. But when the weight is the same, the material doesn’t matter.
✅ Answer: They both weigh 1 kg.
