The+Physics+of+Daily+Life

This page can be used to ask physics questions that come up in your life

 * I was just wondering when your tires squeal, like when you take a turn too fast, what exactly is happening?**
 * **FN:** You would squeal, too, if you were dragged too fast across the pavement.


 * What are the physics of a dreidel?**


 * What are the physics of a yo-yo?**
 * **FN:** We will do this soon, once we start rotational dynamics.

> For more info on baseball physics, including slo-mo videos, see: [|http://webusers.npl.uiuc.edu/~a-nathan/pob/] > The JJHS Library also has the famous book [|The Physics of Baseball,] If anyone wants to borrow it, it's at //796.357 ADA//
 * What are the physics of a curveball?**
 * **MondoLax22:** It has to do with the air currents as the pass over the seams of the ball which creates a downward force resulting in the "curve". Where the ball ends up and how the ball appears to the batter is heavily reliant upon the Magnus effect which deals with the nature of spinning projectiles.
 * **FN:** See the quintessential article: http://www.popularmechanics.com/outdoors/sports/1283161.html
 * **EL:** I did a science project partially on this in 7th grade. It was awful. But yeah, it's all about the seams and the initial curve on the ball. I remember one article by some scientists insisted it was actually an optical illusion. While that might not be true, there are some of these in baseball. For instance, many people often say a hard fastball "rises." That's not true. Since it is thrown with such velocity and backspin, it simply does not sink as much as a normal thrown object does, nor as much as we expect a ball to drop. So it stays rather straight while we expect it to go down, while it //appears// that the ball actually rises.


 * Why does bread always land butter-side down?**
 * **FN:** If you are really curious, we can do this as a lab during our rotation unit. (Yes, with real bread and butter!)
 * 1) **Could you please give a more detailed explanation so I can convince my sister that this actually happens?**


 * Does plasma behave any differently than matter in general?**
 * **FN:** By coincidence, the following showed up this evening in my RSS reader about the Plasma Science Expo: http://twistedphysics.typepad.com/cocktail_party_physics/2007/11/the-incredible.html . Jennifer Ouellette writes a great blog, both informative and funny, though probably a bit lengthy for your teenage attention spans.


 * How would one mathematically model a human action (inculding muscle mechanics and muscle capabilities) such as throwing a javelin or shooting a lacrosse ball?**
 * **FN:** This is the goal of a branch of biophysics called //**biomechanics**//. A good introduction can be found on the following university course page: http://www.asu.edu/courses/kin335/ . The labs posted here look good, perhaps we'll do some!


 * The instrument in the image below is called a Guiro. It is played by sliding a wooden stick along the ridges to create a more-or-less pitched percussive sound (I'm sure you know what it sounds like). Why is it that when you slide the stick over the ridges more rapidly, the frequency increases? I understand that the frequency of hitting all the ridges increases (you slide over all the ridges in less time), but that's not what changes the pitch. Picture it this way: imagine you just had one ridged instrument. What would cause the frequency of the pitch created by that to increase?**
 * **FN:** My son has the [|toad guiro] pictured on Wikipedia. Remeber, frequency //**is**// pitch. I will show you a demo called a [|siren disk] that illustrates this concept in a very cool way.