IGCSE Coordinated Science: Conduction

IGCSE Coordinated Science: Conduction

1. Describe experiments to demonstrate the properties of good and bad conductors of heat.

A simple experiment can be conducted to find out whether something is a good or bad conductor of heat!

Prepare a few rods made from different materials. Use wax to attach small pins to their ends and then heat the other end of the rods. The thermal energy will be transferred by conduction, from one end to the other. Eventually the wax will melt (due to the heat from the rod) and the pin falls off.

The best conducting rod will have its pin dropped off fastest because it transfers the thermal energy the fastest!

2. Explain heat transfer in solids in terms of molecular motion.

• Conduction is a type of thermal energy transfer that occurs mainly in solids.
• In any solid object/substance, its particles are fixed in regular structure and they cannot move.
• However, when the solid object is heated, its particles gain thermal and kinetic energy.

  But since they cannot move, they vibrate instead.

• As particles with more kinetic energy vibrate, they also pass on the vibration to other particles too.
• Consequently, the thermal energy is also passed on!

The right of the solid object is heated. The particles begin to vibrate. The vibration is passed on to the particles on the left. The thermal energy is also transferred when the vibrations are passed on.