Recent content by lzh

0=k1x+mx"+k2(x-y)+b(x'-y') 0=b(y'-y')+k2(y-x)+k3*y+u after some more modification, but I'm still unsure...

hi! oops I mistyped... 0=k1x+mx"+k2(x-y)+b(x'-y') 0=b(x'-y')+k2(x-y)+k3(y-u)

Homework Statement consider the mechanical system below. Find the equation depicting the system. u is the input force. sorry for the poor picture, I had to draw it on my tablet... http://img685.imageshack.us/img685/1043/ogataprob.png Uploaded with ImageShack.us Homework Equations F=ma...

it's the ratio of shear stress to shear strain. G=(F/A)/tan(theta) but truthfully I don't understand what role G plays in this question except for in the phi equation i posted

Homework Statement A thin, uniform, rigid disk of mass M, radius R is welded to a light, elastic shaft of radius r, length L, shear modulus G. Phi is the torsional oscillation. http://img38.imageshack.us/img38/9811/unledlf.png Uploaded with ImageShack.us Homework Equations Phi=TL/GI...

basically those two motors are attached to the frame, and the spinning end of the motor freely rotates. The frame is on a near frictionless spin table, so anything rotation from the motor will cause an opposite spin on the table. And so yea its making the frame spin about a fixed vertical axis...

sorry for the double post. But here are my calculations: assume every rod has mass m. length of the orange/black rod is l and length of blue rod is r. I=12rods*I(orange/black)+8rods*I(blue) I=12*m(l^2/12+l^2/2)+8*(mr^2/3) does this make sense?

hi, thanks for the help! if I were to have two motors spinning on this frame, one on the "top" of the frame, and one on the bottom. Should I be solving for the moment of inertia with respect to the center of mass, or should it be displaced?

Homework Statement This isn't a homework problem but rather a problem I need to solve for a personal project of mine. Basically I need to find the moment of inertia of the following: http://img860.imageshack.us/img860/3952/roboframe.jpg Uploaded with ImageShack.us The rotation is with...

I'm fairly sure that the magnetic field is dc, since it has an ac/dc adapter. I'm thinking of having a microcontroller and various sensors, as well as bluetooth and perhaps a wireless transmitting mini camera. These are all pretty barebone parts from sites like sparkfun, so I don't think that...

So basically i have this powerful electromagnet that generates an electromagnetic field that can levitate another magnet and withhold a load of 12oz and still levitate: My problem is, I want to be able to use electronics and send wireless signals through this strong magnetic field. I can...

I was thinking of finding the integral of the power from 0 to T and then divide everything by T. But for some reason the answer is coming out weird.

Homework Statement A wheel with rotational inertia I is mounted on a fixed motionless axle. The singular speed w of the wheel is increased from 0 to Wf in a time interval T. Net torque=IWf/T What is the average power input to the wheel during this time interval? Homework Equations...

Oh, I see! Thanks, I got it!

So it'd be: 56N(2m)=-dU dU=-112? Am I not getting this?