Question 1: Define conduction and give an example of where it occurs in everyday life.

Answer: Conduction is the transfer of heat through a solid material by direct contact, for example, heating a metal spoon in hot water.

Question 2: Explain how convection differs from conduction in transferring heat.

Answer: Convection involves the movement of fluids (liquids or gases) carrying heat, whereas conduction transfers heat through direct contact within a solid without bulk movement.

Question 3: Describe the process of radiation and identify a natural example.

Answer: Radiation is the transfer of heat energy through electromagnetic waves, such as the Sun's rays reaching Earth.

Question 1: A metal rod with a length of 2 meters and a cross-sectional area of 0.0001 m² is heated at one end. If the thermal conductivity of the metal is 50 W/m·K and the temperature difference between ends is 80°C, what is the rate of heat transfer through the rod? (Use Fourier's law: Q = kAΔT / L)

Answer: Q = 50 × 0.0001 × 80 / 2 = 0.2 watts

Question 2: Calculate the amount of heat energy transferred in 10 minutes through a window that has a heat transfer rate of 0.5 watts. Provide your answer in joules.

Answer: Energy = Power × Time = 0.5 W × 600 s = 300 joules

Question 1: Outline a simple experiment to compare heat transfer by conduction and radiation from a heated metal block. What variables would you control, and what safety precautions should you take?

Answer: A possible experiment involves heating a metal block and measuring temperature changes when in contact with another material (conduction) versus radiating heat to a surrounding surface (radiation). Variables to control include the temperature of the heat source, material type, and distance. Safety precautions include wearing heat-resistant gloves, safety goggles, and ensuring proper ventilation to avoid burns or inhalation of fumes.

Question 1: A city experiences higher temperatures during the day due to increased radiation from the Sun, with minimal conduction or convection involved. Explain how radiation contributes to this temperature rise and why it is significant in climate change.

Answer: Radiation from the Sun transfers heat directly to Earth's surface, increasing temperatures. This process is significant in climate change because increased greenhouse gases trap more radiation, leading to global warming.

Question 1: Discuss how the different methods of heat transfer (conduction, convection, radiation) play roles in the Earth's climate system. Include examples of each process and their impact on global warming.

Answer: Conduction occurs in the Earth's crust where heat from the interior slowly transfers to the surface. Convection happens in the atmosphere and oceans, redistributing heat globally through movement of air and water. Radiation from the Sun heats Earth's surface directly and is affected by greenhouse gases, which trap outgoing radiation, leading to global warming. Understanding these processes helps in developing strategies to mitigate climate change.

Question 1: Explain how insulation materials in buildings reduce heat transfer through conduction and radiation, helping to mitigate climate change impacts.

Answer: Insulation materials, such as foam or fibreglass, reduce heat transfer by conduction and radiation. They trap air and contain reflective surfaces that reflect infrared radiation, keeping buildings warmer in winter and cooler in summer, thereby reducing energy consumption and greenhouse gas emissions.