The Magic Balloon - Thermal Energy and Energy Transfer
A Learning Activity is a strategy a teacher chooses to actively
engage students in learning a concept or skill using a digital tool/resource.
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Phase:
Before/Engage
Activity:
This Learning Activity will be a whole group demonstration. The students will be given the magic balloon document. The teacher will explain that two balloons will be used, one filled with only air and one containing air and water, during the demonstration. First, the students will make predictions about what will happen when the balloons are placed over a flame on their magic balloon document, give the students several minutes to make predictions. Next, the teacher will then hold each balloon over the candle flame and allow the students to make observations and provide explanations for what they observed. The teacher can then lead a discussion about what happened and introduce several topics, including energy transfer and thermal energy.
Assessment Strategies:
Assess student understanding through class discussion and written answers on the magic balloon document. The teacher may use this to probe student understanding of the topic and guide future lessons.
Advanced Preparation:
The teacher will need to gather several materials, including a candle, lighter, balloons, water source, and appropriate safety gear. The teacher will need to practice before class to get the right level of water in the balloons. Remember to take appropriate safety precautions when working with fire. The teacher will either need to make paper copies of the magic balloon or share the document with students via an electronic source. The balloon without water should pop in just a few seconds because the latex will melt quickly, and the balloon containing water will last much longer over the flame before it pops if it pops at all. The water will absorb heat energy and act as a coolant. The warm water will rise to the top and create a convection current that will allow the cooler water to remain closer to the flame and absorb the heat energy, thus preventing the latex from melting.
Variation Tips (optional):
The teacher may choose to vary the amount of water to see how it affects the time before the balloon pops. The teacher may also vary to distance between the flame and the balloon.
Notes or Recommendations (optional):
The students will be highly engaged anytime the teacher uses an open flame. Make sure that the students do not get too close to the flame and use proper safety apparel and precautions. The balloon that contains water will make a mess.