In this video Paul Andersen describes motion as the movement of an object over time. Displacement, velocity and acceleration are all defined. An experiment in motion is used to calculate velocity and acceleration of a tennis ball.

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...

Did you know that centrifugal force isn't really a thing? I mean, it's a thing, it's just not real. In fact, physicists call it a "Fictitious Force." Mind blown yet? To explore this idea further, this week Shini sits down with us to...

In this video Paul Andersen explains how the mechanical energy added or removed from a system results from work. For work to occur a force must act parallel to the displacement of the system. Since work and energy are equivalent the...

Lots of people believe the Universe is infinite, but there's a good possibility that might not be the case. Which means that there would be an actual edge of the Universe. What happens at that edge? Is there a restaurant?

In this video Paul Andersen explains how the gravitational field strength is directly related to the mass of the object and indirectly related to the square of the distance from the center of mass. The equation for gravitational field...

So we've all heard of relativity, right? But... what is relativity? And how does it relate to light? And motion? In this episode of Crash Course Physics, Shini talks to us about perspective, observation, and how relativity is REALLY weird!

Adam Savage walks through two spectacular examples of profound scientific discoveries that came from simple, creative methods anyone could have followed -- Eratosthenes' calculation of the Earth's circumference around 200 BC and...

The full moon might seem bigger on the horizon than when it's higher up, but when does it actually take up more space in the sky?

How do lenses work? How do they form images? Well, in order to understand how optics work, we have to understand the physics of light. In this episode of Crash Course Physics, Shini talks to us about optical instruments and how they make...

Mr. Andersen defines the terms energy, work and power. He also uses a simple example to calculate both work and power.

We’ve covered a lot of incredible stuff, but this week we’re talking about the weirdest objects in space: BLACK HOLES. Stellar mass black holes form when a very massive star dies, and its core collapses. The core has to be more than...

How Big Is The Sun?

In this video Paul Andersen explains how the work is a product of the external force applied to an object or system and the distance it moves. Power is a measure of the amount of work done per unit time. The work can be calculated as the...

Physicists, air traffic controllers, and video game creators all have at least one thing in common: vectors. But what exactly are they, and why do they matter? David Huynh explains how vectors are a prime example of the elegance, beauty,...

Why do some regions experience full-time heat while others are reckoning with frigid temperatures and snow? And why are the seasons reversed in the two hemispheres? Rebecca Kaplan explains how the shape of the Earth's orbit around the...

What are limits? How are they defined? How are they used to define the derivative? What is L'Hospital's rule?

Adam Savage walks through two spectacular examples of profound scientific discoveries that came from simple, creative methods anyone could have followed -- Eratosthenes' calculation of the Earth's circumference around 200 BC and...

Today Phil’s explaining the stars and how they can be categorized using their spectra. Together with their distance, this provides a wealth of information about them including their luminosity, size, and temperature. The HR diagram plots...

Mr. Andersen explains the difference between potential and kinetic gravitational energy. He also uses physics to calculate the energy in various objects.

Your mortal enemy has captured you and hooked you up to a bizarre experiment. He's extended your nervous system with one very long neuron to a target about 70 meters away. At some point, he's going to fire an arrow. If you can then think...

In today's episode, Phil looks at how gravity plays out across the universe.

I took a trip to one of Austin's famous moontowers so I could put the enormity of our solar system into perspective. With the help of a grapefruit, and a lot of walking, you'll get an idea of just how tiny everything is out there!!

Down here, on Earth, if you look up at the night sky, it seems like all the stars up there look the same. Or maybe at least similar. But, it turns out that stars are very different and we shouldn't stereotype them. Some are bigger, some...