A double glazed window has two sheets of glass with a sealed gap between them. The gap is filled with argon gas. Why does the argon gas reduce the rate of energy transfer through the window?
argon gas is denser than air, so energy passes through the gap more slowly
argon gas is transparent, so energy from the room is reflected back inside
argon gas is cooler than the glass, so it absorbs energy from both sheets
argon gas has a lower thermal conductivity than glass, so conduction is slower
40 exam-style questions on AQA GCSE Physics 1.2 Conservation and dissipation of energy, covering 1.2.1 Energy transfers in a system and 1.2.2 Efficiency. Each one has a worked solution and a mark scheme showing where the marks go.