This P4 class got “heated” up with our hands on activities. Both schools are currently on the topic of Heat, and what good way to have some “heat” in the class. The weather was cooling too!
1st experiment. The class was taught how to read markings off a thermometer, taking note of avoiding parallax error (not reading markings at eye level). The first reading was always boiled water and we cautioned the girls to avoid touching the glass beaker. Next, they carefully took turns to drop the ice cubes into the hot water, to avoid splashing of hot water droplets. Observe and record for both variations.
2nd experiment: Class explored the differences between the good conductors of heat and poor conductors of heat. Using 3 different materials, they touched the spoons before placing the spoons into another hot beaker of water, timed them, observed and recorded, with intervals of 1 min, 2 min and 3 min. They were supposed to observe the “hotness” of the 3 materials after the intervals. It was interesting to note that the girls predicted the metal spoon would get hottest after 3 minutes when we asked them to predict whether the spoons gained heat or lost heat at the end of the experiment. To their surprise, they discovered the metal spoon lost heat and were cooler to the touch after 3 min. On the other hand, the wooden spoon and the plastic spoon were warmer than the metal spoon. We helped them to “Think & Link”; metal gains heat fast and loses heat fast too. Non metals gains heat slower and loses heat slower too. As the hot water also loses heat to the surrounding, the metal spoon reacts the same way too. On the other hand, the poor conductors of heat were able to retain heat well and emerged as “winners”. This also helps explains why styrofoam boxes are the best choices to “ta-bao” (packet) food back. The girls were able to understand and link head knowledge and actual situation.
Wrapping up the lesson, we recapped the conductors of heat and gave the girls time to write down their notes.