Thermal Expansion Puzzles
Challenge yourself with these puzzles on thermal expansion. Click the buttons to reveal hints and answers!
Puzzle 1: Why do railway tracks have small gaps between sections?
Think about what happens to metals when they are heated.
The gaps allow the tracks to expand when heated, preventing them from bending or buckling.
Puzzle 2: Why does a metal lid on a jar loosen when run under hot water?
Think about how different materials expand.
The metal lid expands more than the glass jar when heated, making it easier to loosen.
Puzzle 3: What happens to the length of a metal rod when it is heated?
Metals change dimensions with temperature.
The length of the metal rod increases due to thermal expansion.
Puzzle 4: Why are expansion joints used in bridges?
Consider the effects of temperature on the size of materials.
Expansion joints allow the bridge to expand and contract with temperature changes without damage.
Puzzle 5: Why do bimetallic strips bend when heated?
Different metals expand at different rates.
Bimetallic strips bend because the two metals have different coefficients of thermal expansion.
Puzzle 6: Why do telephone wires sag more in summer than in winter?
Metals respond to temperature changes.
In summer, the heat causes the wires to expand and sag more compared to winter.
Puzzle 7: Why is a gap left between the ends of pipelines?
Think about what happens when pipes heat up.
The gap allows the pipes to expand when the temperature increases, preventing damage.
Puzzle 8: What is the effect of thermal expansion on concrete structures?
Consider the rigidity of concrete.
Thermal expansion can cause cracks in concrete if no expansion joints are provided.
Puzzle 9: Why do hot air balloons expand as they rise?
Hot air behaves like other gases.
The hot air inside the balloon expands as it rises, increasing its volume.
Puzzle 10: What is the term for the amount a material expands per degree change in temperature?
It’s a specific property of materials.
This is called the coefficient of thermal expansion.
