 Alright, first of all I have a what direction is it? It's that way. I have the definition for energy at the top of this page just to remind you to keep checking yourself. Like does it make sense that this that energy is the ability to do work and that work is force times distance? Like just keep checking yourself and really I think that there are three main categories of energy that we're gonna look at or consider in this class and I I don't know if this is an official way to sort the different types of energy but for my brain it's I think it's helpful. I'm gonna give you the big categories first and I'm gonna tell you that we're gonna name seven types of energy or set seven categories of energy and this list is not comprehensive so I've picked the kinds of energy that will help us in this class or help us with biological concepts. So the first kind of energy we've actually already talked about and it's a big category like many other kinds of energy sort of fall under this umbrella and that is the energy of movement. Go ahead think about I know you know what this is. It's kinetic energy and remember we talked about kinetic energy when we talked about molecules and atoms we were in chemistry land and we were talking about that the speed of the molecules their own like kinetic energy was we could measure that by measuring temperature and all atoms and molecules have this kinetic energy they're all moving so kinetic energy is the energy of movement so anytime something is moving it has kinetic energy our other big category and I'm gonna put this I don't I wish I hadn't numbered them or maybe I will will number them this is number three I don't know if I like my numbering I'm probably gonna want to re-number it after we get done with this. Kinetic energy to me energy of movement is sort of opposite of something called potential energy and that is truly like it really is like possibility it's energy and waiting stored energy let's call it stored energy and that should mean absolutely nothing to you until we look at some examples and I I can't help it I think we should probably look at our examples gravitational potential energy is the energy that you know if you have something you're holding something above the ground it's not moving it's not doing work on anything but if you drop it it will move and it will possibly it could it could apply a force to something as it's moving and do work on that thing so gravitational potential energy is an energy of position if you're at the top of the hill you have a lot of gravitational potential energy that potential energy gets transferred into kinetic energy transformed into kinetic energy and we'll talk about energy transformations which are super cool as well but to me gravitational potential energy is the most I don't know the most intuitive kind of potential energy but the other one that is probably more important for us is chemical energy and chemical energy is a form of potential energy but it's energy and again this is like this is weird and we'll talk about this in more detail but it's energy it's stored in chemical bonds put a fork in that one we're we're definitely gonna come back to it there's a reason that I numbered this one and three because I'm gonna put number two in here right now and this one I I feel a sadness I have a sadness to name this one because I have absolutely nothing to say about it except oh my gosh it's super cool light energy I have no idea what it is it's the ability to do work I can't visualize that I I have no idea light energy you're on your own however light energy think about a biological system in which light energy might be super important well all of our biological systems almost all of them rely on light energy from the sun and the process of photosynthesis which takes that energy from the sun and uses it to build sugar molecules for us to eat that's all we're going to say about that there's going to be this like light energy fuels all these other kinds of energy light energy fuels living systems awesome we'll see it a lot but I can't tell you like what it is I think it's a really weird one I look forward to my oldest son going to college he's going to study biochemistry and physics and molecular biology I can't remember what his major is but I bet he'll learn some stuff about light and then I'm excited for him to teach me what he learns in the meantime we're going yeah we know what it is and that's good enough for us this leaves us with a couple types of kinetic energy that I want to talk about and one of them we've already discussed that was thermal energy and remember thermal energy was the maybe we didn't name it thermal energy but that energy of movement in those molecules the faster they go the more thermal energy they have do you see how it's actually a category of kinetic energy because it's an energy of movement the other one that I want to talk about briefly and again in a detail that is biological not physics illogical and that is electrical energy that says electrical it does I promise electrical energy I'm gonna give you a definition on this because you might be like dude electrical energy is not biological it is in wires and lighting up lights and whatever running our computers and phones and stuff true story and we absolutely are electrical critters who knew and if you stick with me we'll learn way more details about that electrical communication but electricity is moving charged particles you see why I put it under the kinetic energy category particles now think about this for a second moving charged particles in a wire are actually electrons moving through the wire bouncing from atom to atom in the metal whatever getting hot and emitting light super cool super interesting in what are charged particles in biological systems ions and in fact all your neural function happens because of moving ions in your neurons so all this all of this this coming at you through the computer is happening because there are a whole bunch of moving ions in my giddy up there's another one one more I have one more for you it is another still a form of kinetic energy but I want this in your um in your whatever pile of things want it in your pile please sound sound energy is it is the movement of molecules it's the movement of well I mean I guess if we were underwater we can still hear sounds underwater and it's the movement through like sound waves that hit our ears and then our that is translated into sound in our brain but it's movement it's waves it's actual like have you ever stood in front of a really really loud speaker and you feel like you can feel it you can feel the sound it actually is these air molecules are moving in waves because of the I don't know how we generated that sound like whatever vibrations the vibe feel when you're talking there's vibrations that are being generated that are moving the air molecules that hit your eardrum and translate a message into your brain okay for our I'm gonna give you uh the things that we're gonna spend most of our time on today probably most of it is chemical energy I'm gonna throw light in there as well because the light energy is um gonna fuel photosynthesis and it's it's the starting point for all energy in living systems okay how do you feel all right we'll um talk about some of the rules of energy next