Nov 16, 2022

Electricity and Magnetism

Ever wondered what’s inside a magnet?

Atoms! The building blocks of matter. At the center of each atom, there is a nucleus which is made of protons (positively charged) and neutrons (neutrally charged). The outer region of the atom has mainly empty space and electrons.

At the microscopic level, there are loads of electrons whizzing around in the atoms of any solid, and a magnet, in this respect, is no different. In a magnet, the unmoving, steady charged particles produce an electric field in which attraction and repulsion forces are felt by other charged particles.

So here’s the cool part: when this charged particle starts to move, it produces a steady magnetic field, which attracts/repels other moving charges. This magnetic field is generated due to the charge in any particle (proton or electron). The positive charge on the proton, and negative charge on the electron each indicate a certain behavior.

Electrons have a certain behavior called “electron spin” in which the electron behaves as it is spinning on its axis while orbiting the nucleus, or even moving for that matter. This is why a moving electron has a magnetic field around the electron. In atoms, electrons spin in usually happen in pairs so if the electrons in the atom have opposite magnetic fields, meaning they are spinning in different directions, then the magnetic field will cancel out.

Unpaired electrons usually will have a slight magnetic field because atoms have strong magnetic properties. In most materials magnetic fields of atoms point in random directions canceling out, however, in some, magnetic fields of atoms are aligned creating a magnetic domain. The direction of the domain depends on if the material is magnetized or not magnetized.

If the material is not magnetized the domains all point in random directions, canceling out. However, if the domains are all pointing in one direction, the domain becomes a magnetic domain. The magnetic domain acts like a bar magnet with a north and south pole. This means that this material is magnetized and has strong magnetic properties. This is known as ferromagnetic material, also known as magnets.

If a charged particle accelerates (moves faster or slower or changes direction because acceleration is velocity by time and velocity changes with direction) it produces both an electric field (because the particle is charged) and a magnetic field (because the particle is moving). As the particle is accelerating, the motion of the particle is changing which means the electric field is unsteady.

The vibrating electric field creates a new magnetic field and the unsteady magnetic field produces a new electric field. Now that the vibrating electric field and unsteady magnetic field have been made the excess energy has to be given off, so it radiates out as an Electromagnetic Wave. The collapsing and regeneration of the electric and magnetic fields is what allows EM radiation to propagate. High speed, electrically charged particles, called Auroras, get close to Earth’s surface and interact with atoms in the atmosphere.

The solar wind pushes against Earth’s magnetic field and surrounds the magnetic field. The solar wind particles come from the sun, and because the Earth rotates on its axis, the solar wind constantly reshapes Earth’s magnetosphere. This cannot happen if the object does not have magnetic fields because the solar wind particles only drape themselves around objects that are electrically conductive. The Earth’s molten and convected material, located in the core, gives Earth its magnetic field which is why the Solar wind shapes the magnetosphere.

This magnetosphere is essential, because it is shielding us from all of these solar wind particles. These atoms give off light, making a glowing region in the atmosphere caused by solar winds (Charged particles from the sun). We know this glowing region as an aurora. A charge which moves (already has an electric field) has a magnetic field around it. Electromagnetic waves, WiFi, microwave, cell phone, (energy travels in ways), radio waves (AM,FM,TV), x-rays.

The only difference between all these waves is wavelength. Longer wavelength = lower frequency. Colors are the way your eyes tell you different electromagnetic waves are approaching you. We only see the visible spectrum. Some animals use infrared to find predators as infrared shows body heat. Animals like butterflies and elk can see ultraviolet rays which they use to navigate. The Sun. The sun blasts the whole range of electromagnetic waves. The sun looks white because it combines all colors of the visible spectrum.

The color you see is the color that’s being reflected. Essentially, the color that the object reflecting it doesn’t need. If you had a favorite plant and you loved it, what color would you shine on it? NOT green! Green is the thing that it’s reflecting, making it the only color that the plant does not need. Black absorbs all, white reflects all. Shining different flashlights at white and black paper is a good example.

White looks white because it reflects all colors and is the combination of all colors in the visible spectrum. Writing with a blue marker is like a blue “blocker” because it blocks all blue light and reflects it. What is the atmosphere? The atmosphere is just a layer of gasses which helps us keep friction so big asteroids don’t hit us, unlike the moon. ROYGBIV → hydrogen and nitrogen are really lightweight and resonate at a higher frequency because blue has an extremely low wavelength. The nitrogen and oxygen resonate with the higher frequencies, in this case blue and violet. At sunset, the sun moves to the left, so it has to go through a lot more atmosphere. All the blue and violet run out, so what’s left is red and orange, which makes a sunset.

There’s no more energy left with the higher frequencies, such as indigo and violet. Why is a fire a spectacle at sunset time? There’s way more particles in the air, so the blue light runs out even quicker, making only red and orange light be reflected. When the window fogs up there’s all different sizes of particles, so it reflects all the range of particles, as white (because white reflects everything.