gravity

Showing 45 posts tagged gravity

That moment that ketchup transitions from a solid, high up in the ketchup bottle, to a liquid that squirts all over your fries – that moment is a big physics moment. Why? Ketchup is a non-Newtonian fluid (like oobleck, peanut butter, custard, toothpaste, paint, blood, or quicksand) that can switch between a solid and liquid state, and ketchup is non-Newtonian in two different ways…

In that transition moment, ketchup may be responding to a strong, quick force, suddenly making it thinner, or if you’re patient and apply just a wee bit of force, it may start flowing given some time and gravity. Grab a ketchup bottle and get the details in this TED Ed lesson by George Zaidan, with animation by TOGETHER.

Related watching: oobleck, TED Ed, the incredible physics of ants, and more about that sugar in your ketchup.

Discovered by German physicist Helen Sperl in 1891, popularized in 1950 by Danish engineer Werner Ostberg, and demonstrated here by Grand Illusions' Hendrik Ball, this is a Tippe TopWatch as it spins “at a high angular velocity,” turning itself upside down to spin on its stem. But wait, there’s more

The interesting thing is that when the Tippe Top inverts, it also changes the direction of the rotation! In other words, at some point during the inversion, the top stops spinning around the axis through the stem and then starts to rotate the other way. At the same time, the center of mass is lifted, and the top is thus a quite interesting problem concerning conservation of energy and angular momentum.

There’s more physics and toy videos in the archives, including another from Grand Illusions: the Spiraculum.

A few marble machines are clickity-clacking in our archives, but never have we seen ones that are designed as laser-cut, flat-packed, wood DIY kits! Hopefully on sale soon from RetroTime.org, a hand cranked Kit2 Marble Machine, above, and a hand cranked Modular Marble Machine - Shield no.2, below: 

There are more kit videos on RetroTime’s YouTube channel.

And in our archives: marble machines and Rube Goldberg machines, including the increasingly-difficult-to-find-on-the-internet Pitagora Suitchi.

via The Awesomer.

How Do We Know How Old the Sun Is? The Royal Observatory, Greenwich, and animation studio Beakus join together to explain how Kepler and Newton’s laws help us figure out the weight of the sun, how the age of our solar system can be calculated by studying meteorites, and how that data helps us determine the sun’s age.

Previously from the Royal Observatory Greenwich, Measuring the Universe, and more videos about the sun.

Circus performer Angelica Bongiovonni rides a Cyr wheel in Cirque Éloize. According to their site, Bongiovonni is one of around 100 acrobats that practice the Cyr wheel in circuses, street performances, and performing art schools around the world. Regarding her first attempt at riding, she explains

It really wasn’t fun. [laughs] It’s kind of like learning how to walk again or ride a bike. It’s a really weird feeling and I just fell all the time. I had so many bruised hips and knees. I’d lose control of the wheel and almost hurt people in the studio. I actually hit myself in the face and got a huge busted lip… It takes hour and hours of practice…

There’s more practice and more tricks in the archives, including Selyna Bogino foot juggling five basketballs. Bonus spinning: camera on a hula hoop.