Which classroom demonstration helps students understand how the earth's surface converts sunlight into infrared energy that warms the atmosphere?

• A. Pouring hot water into a jar to observe evaporation.
• B. Using a thermometer to measure cold and hot days.
• C. Painting a model of the earth to show continents.
• D. Demonstrating solar energy using black paper in glass jars to observe infrared warming.

Answer: (D)

Sunlight energy absorbed by the Earth's surface is converted into heat, warming the air and radiating infrared energy into the surrounding atmosphere. The demonstration with black paper placed inside glass jars exposed to sun shows this process clearly: the dark surface absorbs more solar energy, heating the air inside the jar, and the glass traps some of that heat, making the warming easier to observe. This mirrors how the Earth's surface absorbs sunlight and heats the air above it, with infrared radiation contributing to the overall warming of the atmosphere. The other activities don’t model this transfer mechanism—evaporation focuses on phase changes, measuring temperatures on hot and cold days shows results but not the absorption-to-warming process, and painting a globe doesn’t demonstrate energy transfer.