We've talked about AC Circuits, but now it's time to delve into the world of AC Circuits (or alternating currents). We’ve talked about how they change voltage, which helps transmit electricity over long distances, but there’s so much more to the physics of AC circuitry.

Hans Christian Oersted had just discovered the connection between electricity and magnetism. Meanwhile, a French physicist named André-Marie Ampère was experimenting with some wires, trying to learn more about the connection between currents and the magnetic fields they create. Ampère would discover one of the most fundamental laws of electromagnetism: what we now call Ampère’s Law.

It's time for the end. At least the end of our first series on physics here at Crash Course. In this episode of Crash Course Physics, Shini sits down to talk about astrophysics and cosmology. By using what we've learned this year, we can better understand our universe. Join us for this final episode of Crash Course Physics as we head into the final frontier.

By now you know your way around a basic DC circuit. You’ve learned how to simplify circuits with resistors connected in series and parallel with a single battery source. But a lot of the real-world circuits that you encounter — and will have to describe — are much more complicated. For example, what happens when there are MULTIPLE batteries, connected in ‘parallel’? And what happens when we add ‘capacitors’ into the mix, with resistors in our DC circuits? On this, our last go-round inside a DC circuit, we’ll encounter junctions, loops, and capacitors!
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How does Stranger Things fit in with physics and, more specifically, circuit analysis? I'm glad you asked! In this episode of Crash Course Physics, Shini walks us through the differences between series and parallel circuits and how that makes Christmas lights work the way they work.

COLLISIONS! A big part of physics is understanding collisions and how they're not all the same. Mass, momentum, and many other things dictate how collisions can be unique. In this episode of Crash Course Physics, Shini sits down to lead us through an understanding of collisions. Plus, she brings along our old friend Sir Isaac Newton.

Batteries power much of your daily life, so today we're going to talk about how they work. We're also explaining how terminal voltage results from the natural internal resistance of every real battery. We'll get into both series and parallel circuit configurations, and how the laws of conservation affect the current and voltage for each.

CALCULUS! Today we take our first steps into the language of Physics; mathematics. Every branch of science has its own way to describe the things that it investigates. And, with Physics, that's math. In this episode, Shini talks us through derivatives and how calculus helps us to understand the world around us.

Moving on to our unit on the Physics of Electricity, it's time to talk about charge. What is charge? Is there a positive and negative charge? What do those things mean? In this episode, Shini talks about electrostatic forces, electrical charge, Coulomb's law, and the force between charged particles.

So, electric current works like a river... kinda... Instead of flowing based on elevation, electric current works a little differently. But it's a good metaphor. In this episode of Crash Course Physics, Shini talks to us about electric current, voltaic cells, and how we get electric charge.

As we learn more about electricity, we have to talk about fields. Electric fields may seem complicated, but they're really fascinating and a crucial part of physics. In this episode of Crash Course Physics, Shini chats about capacitors, conductors, electric field lines, and how objects with net charge generate electric fields.

One of the greatest inventions is the steam engine. But why? What makes it so useful? And how does it work? In this episode of Crash Course Physics, Shini talks to us about how engines work, what makes them efficient, and why they're pretty cool.

In this episode of Crash Course Physics, Shini is very excited to start talking about fluids. You see, she's a fluid dynamicist and mechanical engineer, so fluids are really important to her. Actually, they're really important to anyone studying physics. So, let's start down this path of understanding, not only how fluids work, but what they are!

Today, we continue our exploration of fluids and fluid dynamics. How do fluids act when they're in motion? How does pressure in different places change water flow? And what is one of the motion annoying things about filming outside on a nice day? I'll give you a hint on that last one... it's lawnmowers.

In this episode of Crash Course Physics, Shini talks to us about how fluids in motion are really, really, REALLY powerful things.

Why is it hard to move a heavy bookcase across a carpeted floor? And why is it easier to keep it moving than it was to get it started moving? You might think it's all about weight, but actually it's about friction. Two kinds of friction! In today's episode of Crash Course Physics, Shini Somara tells us about Static and Kinetic friction; how they work and how they're different.

LIGHT! Let's talk about it today. Sunlight, moonlight, torchlight, and flashlight. They all come from different places, but they’re the very same thing: light! It’s what makes it possible for us to see the world around us, so it’s worth a close, hard look. For instance, how does light travel? When you flip that switch in the bathroom to brush your teeth, how does light move from the light bulb, to the mirror, and into your eyes?

In this episode of Crash Course Physics, Shini talks to us about how power gets to our homes. It's kind of amazing when you think about it and much more complicated than it may seem!

In this episode of Crash Course Physics, Megneto helps Shini explain what induction is, how it works, and why magnetism is so seemingly complicated.

Continuing with last week's calculus introduction, Shini leads us through how integrals can help us figure out things like distance when we have several other essential bits of information. Say, for instance, you wanted to know how far your window was off the ground. You can figure that out by using integrals, a tennis ball, and a stopwatch! It's all here in this episode of Crash Course Physics!

How the heck do we map out a planet without oceans? NASA had to figure that out when we sent the Mariner 9 probe to Mars. There's some tricky, yet fascinating science behind all of it! In this episode of Crash Course Physics, Shini talks to us about sea level, kinetic theory, and phase changes.