Intro

For a little over four years in college I studied Computer Engineering. It was really great, I was able to study everything from analog circuit design, microprocessor design, operating systems, networking, and look at that, I can already see some eyes glossing over. I haven't even mentioned the math classes I took. OK, let's try this. Who has a cell phone? Digital Camera? An mp3 player? PDA? These things require some energy in order to function, right? Where does their energy come from? Batteries.

Let's talk about batteries for a second (draw simple circuit diagram of battery connected to a cell phone). There are many sorts of batteries, they all have a specific voltage. Stay with me here. Another way to say voltage is electric potential. Let's talk about potential for minute. That potential they have is important. When designing a cell phone or a camera (they are really just special purpose computers), you have to be careful not to waste the potential of the batteries that power them. How to squeeze more work out of smaller and smaller batteries is a major engineering challenge right now. Even more disastrous than wasting potential is to short circuit that potential. Have you ever stuck your tongue on a 9V battery? Wasted potential right there. You have to make sure all the battery's potential is converted into something useful, lighting up displays, sending a signal out through an antenna, filtering out noise, compressing image data--has anyone used a laptop that you really couldn't keep comfortably on your lap? The laptop's battery was being used to produce heat. Wasted potential. That's important, a battery's potential should be converted into useful work.

One more interesting thing about the batteries most of our gadgets use is that their charge, their potential, really isn't their own. It comes from a much greater source of potential. Your wall, right? No, huge generators of potential: dams, nuclear or coal power plants, maybe even the sun. Sources of electric potential.

Now let's talk about us. We have potential and a great work to do with that potential. Much of this lesson will come from the Stake Priesthood Leadership meeting with Elder Russell M. Nelson that was here a couple weeks ago.