Conduction – Floor vs Mat

Objective: To demonstrate the experiential process of heat transfer through conduction and its effect on materials with air pockets acting as insulators. 

Outcome: Students will learn to observe  Conduction  that occurs commonly in everyday life 

Requirements: A mat laid in a corner of the classroom

Prerequisites: A conceptual knowledge of processes of heat transfer

Note:Conduction is the process by which heat energy is transmitted through collisions between neighbouring atoms or molecules. Conduction occurs more readily in solids and liquids, where the particles are closer together than in gases, where particles are further apart.

Procedure: 

Step 1: Let the class lie down on the  floor in mid afternoon

How does it feel? Hot or cool?

Step 2: Discuss how the direct body contact with the floor cools the body. Normal temperature of the body being hotter than the floor, heat travels from the hotter body  to the cooler floor via conduction thereby cooling the body

Step 3: Next lie down one by one on the mat. Or place one foot on the floor and the other on the mat. Does it feel cooler than the floor? Why not? Discuss how the mat with air gaps acts as an insulator/thermal barrier preventing direct heat transfer to the cooler floor. Now imagine the heat trappings in a coir bed or a foam bed in a hot climate.

Figure: Body cooling down by sleeping on the floor is due to  heat transfer through conduction process

Reference: http://www.fairconditioning.org/resources/#126-module-ppts-1478947081