So You’re Underwater: Why Do You See That Circle of Light Above You?
Have you ever sat on the bottom of a swimming pool and pondered your watery ceiling? Most of the surface is a sheet of light blue, and you can’t see …
dot physics
Tuariki Delamere’s Somersault Could Have Launched a New Era in the Olympic Long Jump
However, since this force is applied at the feet, far from the center of mass (r > 0), it’s going to produce a torque. In this case, the torque would …
The Incredible Physics of Simone Biles’ Yurchenko Double Pike
A gymnast can actually perform both of these types of rotation at the same time—that’s what makes the sport so interesting to watch. In physics, we would call this type …
No, You Can’t Have a Solar-Powered Passenger Plane
The angle at which the light hits the panel, θ, is measured from a line perpendicular to the surface. This means you will get a maximum solar panel power when …
How to Run on the Moon
When the elevator is stopped, the two forces are equal and opposite, and the net force is zero. But if you’re accelerating upward, the net force must also be upward. …
If Betelgeuse Explodes, Just How Bright Will It Get?
Theres a famous star that I’m sure you’ve seen in the sky. Its name is Betelgeuse, and you can find it in the Orion constellation, where it marks Orion’s right …
What Kind of Battery Would You Need to Power a Lightsaber?
Melting an ice cube takes 3.34 x 105 joules per kilogram. So a single ice cube with a mass of 50 grams would take 16,700 joules. You can already see …
Can You Really Run on Top of a Train, Like in the Movies?
Just because you see something done in a movie, that doesn’t mean you should try it yourself. Take, for example, a human running on top of a moving train. For …
Can You View a Round Solar Eclipse Through a Square Hole?
If you live in the US and missed the last total solar eclipse in 2017, good news! You’re about to get another chance. There will be a total solar eclipse …
How Do Heat Pumps Work?
Now stretch it really hard and quickly hold it to your upper lip, which is sensitive to temperature. You will feel that it’s warmer than it was before. That’s because …