Introduction
In this chapter we will develop our understanding of the heating and cooling processes we looked at in KS3, which transfer energy within a material or from one object to another. We will investigate thermal conductivity and the differences in the processes of thermal conduction in metals and non-metals.
We will look at how we can design object to either increase the effectiveness of this transfer of energy where we want it to happen and how we can use materials to help us stay warm by reducing the loss of heat.
Specification links:
Task 1: Know
Task 1a: Use look, cover, write check and quizlet to learn the answers to the core questions and the keywords for this topic
Learn
Task 2: Thermal energy transfers
Task 2b: Make notes that:
Define conductors and insulators.
Describe and explain conduction.
Describe and explain convection.
Task 2c: Watch the video and copy and complete the paragraph.
When the metal rod was heated, the _______ received more energy. This meant they _____ more and ______ with each other. This passed the ______ energy along the rod. The movement of thermal _____ like this is called _________.
Task 2d: Watch the video and copy and complete the paragraph.
When a ____ is heated, the particles gain ____ energy. The particles in the fluid spread out and become _______. The hotter particles rise up, and the _____ (more dense) particles _____. These now get heated and the cycle is repeated. This process is called __________.
Task 2e: Complete and mark the exam question
Answer
Air is a good insulator (or air is a poor conductor)
So it reduces conduction (not stops conduction)
Trapped air reduces (or stops) convection
Set 2&3 go to task 4 now
Task 3: Infrared radiation - Set 1 only
Task 3b: Make notes that:
Explain what infrared radiation is
Describe the relationship between infrared radiation and the temperature of the object
Define black body radiation
Describe uses for infrared radiation
Describe how the temperature of the Earth is affected by the balance of absorbed and emitted radiation
Task 3c: Answer these questions:
What would happen to the temperature of an object if it was emitting energy at the same rate as it was absorbing it?
What would happen to the temperature if the absorption and emission rates were different?
Can you think of an example where this happens?
It would remain at a constant temperature (it is in thermal equilibrium)
Initially it would change temperature. This would affect the rate of emission. Eventually the rate of absorption would become equal to the rate of emission (= thermal equilibrium) the temperature would then remain constant
The ground on a sunny day will increase in temperature when the sun comes out because initially it absorbs the radiation faster than it can emit it
Task 3c: Complete and mark these exam questions
Task 4: Specific heat capacity
Task 4b: Make notes that:
Describe the differences between temperature and thermal energy.
Define specific heat capacity
Explain how to calculate the energy required to change the temperature of an object.
Task 4c: Complete the SHC worksheet
Task 4d: Complete and mark these exam questions
Task 4e: Complete the progress quiz:
Task 5: Specific heat capacity required practical
Task 5b: Make notes that:
Define specific heat capacity.
Write the method for an investigation to measure the specific heat capacity of a material.
Draw and label a diagram of the equipment required
Explain why the value calculated in the experiment may be higher that actual specific heat capacity
Task 5c: Complete and mark this exam question
Task 6: Thermal insulation
Task 6b: Make notes that:
Explain how the following reduce thermal energy loss.
Loft insulation
Cavity wall insulation
Aluminium foil behind radiators
Double glazed windows
Explain how to calculate the payback time of a simple home improvement feature.
Write a method for an investigation to find out how the shape of an object affects the rate of heat loss.
Task 6c: Copy and complete this tables:
Based on payback time which methods are the best?
Task 6c: Complete and mark these exam questions
Task 7: Summary
Task 7a: Watch the videos:
Task 7b: Read through the BBC Bitesize revision pages and have a go at the quiz
Task 7c: Complete the seneca learning unit for your set.
Task 7d: Make a mind map or single page revision summary of this topic and add it to your revision folder. Use the specification to help you.
Specification links:
Task 8: Check
Extend
Example exam questions