Answers to AQA GCSE Conduction

Answers to Practice Questions

1.State the names of 3 conductors and 3 insulators

Conductors:

Metals, alloys, graphite, any named metal, any named alloy.

Insulators:

Any non metal, except Graphite. 

Examples: plastic, polystyrene, paper, wood, wool, cotton. 

The list for insulators is only a guide as there are many insulators. 

2. A manufacturing company is designing a new saucepan, should they use a material with a low or high thermal conductivity, explain your answer.

High thermal conductivity

This is so that the thermal energy can be conducted through the saucepan quickly to reach the food inside.

3. Describe how insulating ski wear is designed in order to reduce heat loss whilst being worn.

Ski wear has low thermal conductivity to reduce conduction and heat loss from the wearer.

Ski wear has thick layers of insulating material to reduce heat loss. 

4. A cooking pot contains a stew at 90°C . Sam suggests that if the cooking pot is placed into a larger container of water, it will allow the stew to cool down faster to room temperature, than if it is allowed to cool just using air surrounding the cooking pot. Explain in terms of thermal conductivity why Sam is correct. 

If the stew cools down faster when the pot is placed in water, than air, this means that water has a higher thermal conductivity than air.