 Okay, we've got the pen working, so let's look at, first of all, let's go ahead and write down a definition of energy as the ability to do work. And again, okay, what is work? Well, if we're talking about a physics perspective, work is distance times force. Okay, so think about this. To do work on something, it requires energy to do the work. And if you do work on something, you move it a distance by applying a force. And if that works for you, you know, push against a table, you apply a force to the table, you move it a distance. When we start thinking about energy inside our bodies, we're actually moving molecules and moving enzymes and proteins. And that counts as doing work. If you're moving molecules against a concentration gradient, for example, you're actually doing work on those. Energy comes in flavors. And so we can have, for example, kinetic energy. And we've actually already talked about kinetic energy. I'm just going to not write the word energy 800 times. Kinetic energy, as you know, is the energy of movement. We know that all molecules have kinetic energy. The more kinetic energy they have, we can measure that kinetic energy in the molecules by taking the temperature of something that tells us the amount of kinetic energy that something has. Have you heard of potential energy? Kinetic energy is the energy of movement. Potential energy literally is, it's almost like stored energy. My best example of kinetic energy is holding a ball above the ground. And it's considered gravitational potential energy. If you hold the ball above the ground, you're not moving it, so the ball itself does not have kinetic energy. But if you drop it, and you move your hand out of the way, you didn't do any work on that ball. Gravity is going to apply a force to the ball and cause it to drop. And so the ball is moving, and we actually have, you can make work happen if you can capture that potential energy. Whoa, think about that for a second. Okay, so you drop a ball. Let's say I dropped a ball from here onto my hand. The dropping of the ball, if there's enough force applied to my hand when it hits from the ball that was dropped, I can actually move my hand. I can do work on my hand. Potential energy, okay, I'm about to blow your brain apart. I really don't want to, but we know that we can have potential energy in the form of gravity. I'm telling you right now that we can have potential energy stored in chemical bonds so you can have chemical potential energy. And I'm going to have lots of examples of this, but chemical energy is stored in chemical bonds. That's how we can visualize this idea of chemical potential energy. And just take a second to think about the food of choice, the very nutritious food of choice that we're going to talk about is gummy bears. Gummy bears, do you agree, they contain energy and it's actually chemical potential energy. There is energy stored in the chemical bonds of the sugar molecules that make up the gummy bear. And if we play our cards right, we can actually break apart those chemical bonds and form new molecules and release that stored chemical energy and do something with it. We can capture it, we can do work, which is fantastic. Some other forms of chemical energy, I mean some other forms of energy. First of all, chemical energy, dude, we're going to be talking about that one a ton. I'm not even going to bother writing all these down. Mechanical energy, except I am writing this one down. Mechanical energy is the energy of something actually moving. Like mechanical things are applying force. And so that is, you know, if you apply force to something, then that's an example of mechanical energy. Radiant energy is light. We're going to talk about light energy. Dude, seriously, energy is so weird. Electrical energy. What? It is electrical energy. Oh, my gosh, this is fantastic. Electrical energy is basically moving electrons, moving charged particles. If you have movement of charged particles, you're going to end up with electrical energy in that light up there that, whoa, I shouldn't have looked at that thing. Heat is another one that we're definitely going to talk about. Heat is a form of energy. This is what we describe, heat. It's movement of molecules, so it's a form of kinetic energy. It's not very organized, and really it's kind of a waste product of energy, and we'll talk about that in more detail in a second as well. Nuclear energy. We are going to talk about nuclear energy today. So these are just some examples of different forms of energy. We're going to look at gummy bear energy and talk about what is the energy inside the gummy bear and how do you get that energy out of a gummy bear?