Energy Transfers I

Task 1 - Recap

Remind the person next to you:

• Why copper is a better conductor than glass.

• Why evaporation has a cooling effect.

• The factors which can affect the rate of transfer of thermal energy.

• How a vacuum flask keeps a drink warm.

Task 2

Look at this radiator.  Can you think of two (or possibly three) elements in its design that help it transfer thermal energy?

Can you think of a way the transfer of thermal energy could be increased still further?

(hint: think about the colour!)

What method does this heat sink use to maximise thermal energy transfer?  How could the rate of transfer of thermal energy be increased even further?  (answer here!)

Answer the questions above on the sheet provided.

Task 3

Discuss with the person next to you how the cape fox and the arctic fox are adapted to their environment.

Think about:

Are the foxes trying to minimise or maximise the energy transfer to their surroundings?

What features help them to do this?

Your teacher will ask you to share some of your ideas with the class and show you this presentation which helps to explain.  When you are happy you understand, write down your explanation on this sheet.

Use the following terms in your explanations:

maximise            minimise              energy transfer             surface area            ears               large           small           fat                insulation             fur                trapped air            limbs            slender            short          squat          stumpy          thermal

Task 4

Look at the list below.  Which of these helps the human body maximise thermal energy transfer to its surroundings and which helps it to minimise thermal energy transfer?

How does each process work?

          • Sweating

          • Hairs stand on end

          • Shivering

          • Reduced blood flow to the skin