friction
Dot Physics
Category archives for friction
Sport Science, Pulling and Friction
Posted by Rhett Allain on February 9, 2010 Forgive me for all the posts on ESPN’s Sport Science (example: Pulling and Power). I can’t help myself. In the short episode recently, Sport Science compared a football player pulling a sled with huge tires on it to a truck pulling stuff. I think their goal was to compare the power per kg from for…
I can pull more than 3000 POUNDS!
Posted by Rhett Allain on February 9, 2010 Note: This is part of my ongoing attack of ESPN’s show Sport Science. Really, I am continuing to look at the episode where they calculate a football player can produce 57,000 Watts by pulling some stuff. Wait…I don’t want to limit my stuff to Sport Science. I see this stuff all the time. The problem…
Sport Science: Pulling and Power
Posted by Rhett Allain on February 7, 2010 I would like to continue my attack on the show Sport Science – ESPN. In this short episode, they are comparing the power of NFL player Marshawn Lynch with that of a truck. You can watch it here if you would like. There are two things that are not quite right with this episode, first,…
Yo-Yo: Rolling, sliding, pulling
Posted by Rhett Allain on January 27, 2010 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…
MythBusters and the physics of knock your socks off
Posted by Rhett Allain on October 11, 2009 The other myth the MythBusters looked at last week was the phrase “knock your socks off” (along with the dropping and shooting a bullet myth). But before that, let me complain. Maybe it is just me, but I totally cringe when these guys use the word ‘force’. Force probably isn’t the best term to use…
Snow Board Jump Help
Posted by Rhett Allain on September 14, 2009 I really shouldn’t do this. I might be helping someone to set up something dangerous. But, I am going to anyway. Here is a question posted on some forum. (actually, it is from math help forum) “I’m anticipating a good winter this year, one with lots of snow. My yard is sloped quite a bit…
Parkour Physics: Wall Climb
Posted by Rhett Allain on August 22, 2009 Forgive me if I don’t know the official parkour term for this move. This is where you have two walls that are close to each other and you vertically climb them. Here is a shot of Mark Witmer (from Ninja Warrior) doing the wall climb. Doesn’t look too hard, does it? Well, I think it…
More on the Giant Water Slide Jump
Posted by Rhett Allain on August 12, 2009 This Giant water slide video is extremely popular on the internets. Maybe you have not seen it (doubtful), then here it is: This is such an incredible stunt that the very first question that comes up is – fake? or not fake? From my previous analysis, I can say: Even though there is some slight…
Physics of Parkour, or how to run up a wall
Posted by Rhett Allain on August 5, 2009 Parkour: the act of running and jumping like a crazy superhero. I can’t do any of it. But I can analyze it. So, let me start with the wall-flip (or any kind of move that involves walking on vertical walls). This looks like a good example (there are a bajillion on youtube). Pretty cool, huh?…
Moonwalking on the moon
Posted by Rhett Allain on June 30, 2009 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…