Exploring Heat and Light Phenomena Together

Energy is coming to us from the sun in the form of light. Today we explored the question: what happens when light from the sun shines on the earth? Some gets reflected, and some gets absorbed.

The students used light sensors to compare reflection from the water and sand. They also used the digital thermometers to measure room temperature water and room temperature sand.

The students let their computers graph for about ten minutes. We had some difficulty getting the graphs to show the powerful ideas that we wanted the students to be able to infer from data. One of the groups' graphs demonstrated what we wanted them to see, after they had decided to use a less amount of water and sand. Emily had also performed the experiment last night, more successfully, and showed the students the graph that she had created. They saw that water reflects light more than sand. They also found out that sand heats up much faster than water.

New powerful ideas:

• Water reflects light more than sand (sand reflects light less than water).
  
• Sand heats up faster than water (water heats up less quickly than sand).
  

We can use these powerful ideas to explain local weather at the beach, why there are sea breezes and clouds in the afternoon on a sunny day.