Recent content by Giannakoulis

could anyone explain me how is it possible to charge your phone wireless, like this video link?

no its not.. anyway I will wait until the tuesday.. thanks both of you guys

I'm saying that static friction equals to maximum friction, also the static friction equals to centripetal force. So i have Ts=Fc=m*v^2/D and Tmax=μ*Ν (N=weight).. If you replace the speed in the first equation you get Ts=4π²Df²m.. So my equation is: μN=4π²Df²m =>μ*m*g=4π²Df²m.. if i solve this...

@haruspex me too.. My math show me f=5π/2..am I doing something wrong?

its the centripetal force my mistake, Fc=m*v^2/D which equals to static friction if i am correct.

In the figure below we put a small coin on a disc, which rotates at constant frequency f, at a distance D=0.2m by the disc rotation axis. If the coefficient of friction is μ=0.5, then what is is the maximum frequency that can have the disc so that the currency does not slip? g=10 m/sec^2 Anyone...

thanks a lot!

Hey guys.. Sorry for my english, i'am only 16 and it's not my parent language. I need help about a problem on mechanical engineering, and i really appreciated if you can help me out. I assume that I've got a moter currents which gives me out 220-230 Volt trend, and has 1800 bends per minute. Now...