Question

On a cold day, it is hard to open the lid of a tight container. But when you gently heat the neck you can easily open the lid. Why?

• A. On heating glass expands and lid contracts.
• B. Lid expands more than the neck and thus slides easily
• C. Neck becomes slippery on heating
• D. Lids of the bottles cannot bear the heat

Answer 1

Answer: (B)

Lid expands more than the neck and thus slides easily

On a cold day, it is hard to open the lid of a tight container. But when you gently heat the neck you can easily open the lid. This is because the lid being made of metals conducts heat better and faster and therefore expands more than the glass container.