torque

Dot Physics

Category archives for torque

Oak Trees are awesome

In this part of the world, we have oak trees. Technically they are called live oaks – but I don’t get it. Of course they are alive. I was at a soccer game and this is the tree I always look at. Look how far those limbs extend horizontally. That branch is about 12 meters…

Apolo Ohno Physics

It is winter Olympics time and time for physics. The event that I always gets me thinking about physics is short track speed skating. It is quite interesting to see these skaters turn and lean at such high angles. All it needs is a little sprinkling of physics for flavor. Check out this image of…

Yo-Yo: Rolling, sliding, pulling

This is actually been sitting around for a while waiting for me to post it. Here is another short Christmas-toy demo. I am going to pull this yo-yo at different angles and on two different surfaces. Check it out. What is going on here? Let me look at the first case where I pull the…

One of my students showed me this game, Fantastic Contraption. The basic idea is to use a couple of different “machine” parts to build something that will move an object into a target area. Not a bad game. But what do I do when I look at a game? I think – hey! I wonder…

Angular Momentum Example

I showed this demo in class and I was surprised at how cool the students thought it was. They actually thought it was some kind of trick. It is not a trick. Instead, this is an example of the angular momentum principle. If you want to try this yourself, I guess you are going to…

Moonwalking on the moon

Slate’s Explainer has an answer and question post about moonwalking. Here is one of the very good questions answered there. Would it be easier to moonwalk on the moon? The Explainer says “absolutely not” and attributes this to the awkwardness of walking on the moon. The article gives an example of Earthly legs being too…

Was the moonwalk fake? No, not the Apollo landings. I am talking about Michael Jackson’s moonwalk. You got to admit, he had a big impact on a lot of stuff and this is my way to give him respect – physics. I am sure you know about the moonwalk. Maybe you can even do the…

Moment of Inertia Demo

When I was talking about balancing a stick, I mentioned the moment of inertia. Moment of inertia is different than mass, but I like to call it the “rotational mass”. What does mass do? Things with larger mass are more difficult to change their motion (translational motion). A similar thing is true for the “rotational…

Friction Demo with a meterstick

This is one of my favorite demos. Easy to do and doesn’t really require any equipment. The basic idea is that you support a meter stick horizontally with two fingers. Slide your fingers in and they will both meet at the center of mass. Here is a video. Meterstick friction demo from Rhett Allain on…

I saw this video on several places. It shows an astronaut playing with a CD player. I wish I were an astronaut. I would probably not stop throwing up though. It would still be worth it. You can only throw up so much right? (I know the answer to this question). Anyway, this is a…