I know that when a car is taking a turn, the front 2 wheels trace out 2 arcs having the same centre. I also know that the steering angle for the outside wheel is more than that of the inner wheel to prevent the car from skidding. My question is during the turn do the rear wheels trace out the same arcs as the front wheels.
When a vehicle makes a turn, the two front wheels trace out two arcs as shown in the figure below. The wheel facing towards the inside of the turn has a steering angle that is greater than that of the outer wheel. This is necessary to ensure that both front wheels smoothly trace out two arcs, which have the same center, otherwise the front wheels will skid on the ground during the turn.   During a turn, do the rear wheels necessarily trace out the same arcs as the front wheels?
Is it possible to embed a scrollable frame inside a PDF? (This is an end-of-year crazy question)   Is it possible to embed a (scrollable) frame or a PDF inside a PDF? If so, how to do it in (pdf)LaTeX?  This is something pretty common in HTML (see for example ). Here it is a webpage with PDF frames   Here it is a fake screenshot so you get the idea.  Portable and non-portable (e.g. only-Acrobat) answers are welcomed.     Example of a down arrow below a frame. The up arrow can be on top of the frame and the triangles point up. Let $G$ be a non abelian group of order $p^3$, with $p$ prime.  I'm proving that $Z(G)$ (its center) is of order $p$. I already know how to do it by saying that its order can't be $p^3$, nor 1, and if it's $p^2$ then $G/Z(G)$ is cyclic then G is abelian, Abs!  But I've been reading another way of proving it and the author supposes that $|Z(G)|=p^2$. Then, she says: "$\exists\ x$ outside the center of $G$, of order $p$." Could someone give me a hint? Thanks! First, if you have a better suggestion for title I'm really opened to suggestions, but it is the best I came up with.  If I touch an electric line and the earth, I will get electrocuted.  However, if I touch the positive of a car battery, people told me the same thing won't happen...why is it?  It seems I need to touch the battery positive and the battery ground. How do I tell Finder to always show my Library folder on Mavericks? I thought there was a checkbox to suppress the hiding of my user Library folder on Mavericks, but I can't seem to find it. I appreciate hiding Library by default, but  have missed it being easily accessible.  How can I get the library folder to be visible in Finder, the Finder go menus / file save dialogs without needing to hold down shift? When we lie down, the "back part of the body" is in contact with the bed. 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I can't open/ping any antivirus sites I have a problem with a virus in windows 7, I don't know what kind of virus is infected my OS, I installed kasersky antivirus, and clear all detected viruses. After that I can't open any antivirus sites, can't ping any antivirus sites. example:  C:\Windows\system32&gt;ping kaspersky.com Pinging kaspersky.com [38.117.98.231] with 32 bytes of data: General failure. General failure. General failure. General failure.  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