When Green School Engagement Officers head into classrooms across Nova Scotia to teach students about Energy Efficiency, we also learn a thing or two along the way.
In Grade 4 science, students learn about how light is used and interacts with the environment. Students also have the opportunity to demonstrate their knowledge as they explore energy efficiency using different light bulbs.
The easy way to explain energy efficiency is to have two lamps with two different light bulbs, an Incandescent and a LED. We talk about the different amounts of energy each light bulb uses, by measuring the watts on the energy meters. We also explore and calculate the amount of energy we can save by using an LED light rather than an incandescent.
The next step is to ask them which one is brighter, and their response is almost always LED. Except for one rare occasion when students responded that the light from incandescent light bulb was more brilliant.
I said: "That is strange. Usually, students tell me the LED is brighter, but you're correct, the incandescent does look brighter! I wonder why?"
A student was quick to suggest that the incandescent bulb was brighter since the inside of the lamp was white. The white light was reflecting more light, while the lamp with the LED bulb was black on the inside, so it was absorbing some of the light and not reflecting it.
A light bulb went on in my head as I thought about what the student said. Wow, what an excellent job applying what they learned about the properties of light! This group of students was very keen to explore further and switch the light bulbs between the two lamps.
We quickly discovered together that his hypothesis was correct because now the LED light bulb in the lamp with white on the inside looked to be the brightest light bulb.
Our next step, if possible, would have been to put the two light bulbs in two lamps with the exact colour on the inside of the lampshade, and see which one appeared brighter.
What a great learning experience while applying some of their new grade 4 science knowledge!
~ Natalie McMaster