 So what I would like to do for you now is a demonstration to introduce the concept of magnetism. So we're getting ready to begin the lesson on electrical, optical and magnetic properties. And I want to demonstrate a specific property of magnetism by magnetizing a grape. And so you might ask yourself, wow, are grapes magnetic? And the answer is no. But they will act as a magnet if you place them in the presence of a strong magnetic field. And this property of not being magnetic but acting as a magnet in the presence of a strong magnetic field is called paramagnetism. So you will learn in this lesson that there are three main categories of magnetism that we're interested in. There's the ferromagnetism, paramagnetism and diamagnetism. And so these grapes are going to exhibit paramagnetism. And so the strong magnetic field is going to be produced by this neodymium magnet that I actually borrowed from a hard drive that no longer works. And this magnet I'm going to use to push the grapes around in a circle by exposing them to this magnetic field. And you can see the grapes are not swinging or moving any on their own right now. And now let's show the magnetic field to the grapes. And what you will see is that I am not touching the grapes, but yet I'm pushing them around in a circle. What's happening here is it's not that the grape is paramagnetic. It's the fact that the grape is 70% water and water is paramagnetic. What's happening is the water sees the magnetic field from this neodymium magnet and they're perturbed by that. And to show their distaste, they all align to resist the magnetic force of this magnet. So it's essentially like putting two north ends of a magnet together. So let me show you this one more time. So I'm going to get it going in a circle and then once I have it sufficiently moving, I'll stop it and get it going in the opposite direction. And as you will see, I am not touching the grape. So we've just magnetized a grape.