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Practice questions · Conduction

Passed along, particle by particle.

Six original Cambridge-style questions on what conduction is, the two ways energy is passed on, why metals lead the field, and why fluids barely conduct at all.

Original questions All questions on this page are original work, written in the Cambridge IGCSE style. They are not from past papers. They test the same concepts and skills the syllabus rewards.
The two mechanisms to quote

Vibrations in all solids, electrons in metals.

01
[2 marks]

Define thermal conduction.

  • Conduction is the transfer of thermal energy through a material. ✓
  • It happens without the material itself moving from one place to another. ✓
02
Analysis
[2 marks]

Explain how energy is conducted through a solid that is not a metal, such as glass.

  • Particles at the hot end gain energy and vibrate more strongly. ✓
  • They collide with neighbouring particles, passing energy along the material. ✓
03
Analysis
[3 marks]

Explain why metals are much better thermal conductors than non-metals.

  • Metals contain free (delocalised) electrons that can move through the material. ✓
  • At the hot end these electrons gain energy and move quickly to the cooler end. ✓
  • They carry energy far faster than vibrations alone, so metals conduct much faster. ✓
04
Analysis
[2 marks]

Explain why gases are very poor conductors of thermal energy.

  • The particles in a gas are far apart, so they collide much less often. ✓
  • Energy is passed on only rarely, and there are no free electrons, so conduction is very slow. ✓
05
Analysis
[2 marks]

A student says that during conduction the hot part of a metal bar moves along to the cold end. Explain why this is wrong.

  • The material (the particles of the bar) does not travel along; the particles stay in place and vibrate. ✓
  • Only energy is transferred along the bar, passed from particle to particle (and by free electrons). ✓
06
Analysis
[2 marks]

A metal saucepan is given a plastic handle. Explain why plastic is a sensible choice for the handle.

  • Plastic is a poor conductor (a good insulator), with no free electrons. ✓
  • So little energy is conducted to the handle, keeping it cool enough to hold safely. ✓

Mark this once you have attempted all six and checked your working. It records a Practiced badge on the topic and adds a one-time bonus. Revealing the solutions alone does not count.