Light and Matter pt. 2

January 8th, 2017

Welcome back to the Nerdy Teacher's Corner lil scientists!

Last time we left off, my students were learning about light behaving as a wave. Today is composed of periods 1-7 and an advisory period. This means that classes are roughly 30 minutes each. There's not a lot of time. However, it's the perfect amount of time to finish our Cornell Notes on Light and Matter. Today, we continue our lesson with light behaving as a particle. Students will take notes on page 58 of their interactive notebook. This starts at slide 23 on the Powerpoint I've added on my Resources page. You can click the link below.

Again, this is my mentor's work Ismael Renteria.

Resources

I introduce the subject just a bit and use the following video to elaborate. Quanta is an interesting word for students. I really like YouTube because it's a great tool for students to review information. 

I really like this video because it explains quanta in a way that students can relate to. Cookies! Not only does it relate it to cookies, but I like the way the chunks of energy are labeled by color dependent on high/low energy and high/low frequency. While labeling the electromagnetic spectrum, students have seen that the color purple gives off more energy compared to red. In the video, you see large packets of energy as Violet, Indigo, Blue. Small packets of energy are usually Red, Yellow, Green. This emphasizes energy, frequency, and wavelength with color. 

We continue further into the Photoelectric Effect which confirms Planck's Quantum Theory. Again, I show the kids the following video. This way they have a different voice providing the same information. 

This video also emphasizes large chunks with high energy waves. 

On the Powerpoint, there's a slide that introduces how the speed of light equation goes into Planck's equation. I do show the kids how to do this, however, often times it can we overwhelming. So, we take it step by step. The kids turn to page 57 in their interactive notebook and they will have two good problems to reference back on. The first problem, as you can see from the image below, asks them to use the new equation they have been introduced to. 

I have the students write out the problem first. Once they do, I ask them to circle what we are solving for. On my notes, you can see it's highlighted. We write that on the first part of the four square. They have to write the unit as well. As we move down the four square, this will be an important step. We then underline what we know. Or information that is given in the problem. When students write it, they have to write the symbol for that item. For example, frequency is v, h is Planck's constant, E is energy, c is the speed of light, and lambda is wavelength. This way they remember the symbols when plugging into the equations. Next, we look at what equations they need to use. We rearrange them so that they are just directly plugging in numbers. Finally, we plug in numbers into the last square instead of symbols. They plug into the calculator and then get their answer. Now, if they are unsure what unit to use, they simply look back at box 1. 

Now, the second problem has a little bit more problem solving. We combine using the speed of light equation with Planck's equation. We take it step by step just like the first one. When doing these problems, I just ask the students to follow along. I do emphasize that they plug in the number into the calculator in parentheses to avoid mistakes.

That's all we have today! Tune in next time to The Nerdy Teacher's Corner!