Recent content by harmyder

Why, usually if we cut spring in half, then the constant doubles.

While reading http://www.dartmouth.edu/~sullivan/22files/System_analogy_all.pdf article, i encountered the following sentence: Thus, we see that K is analogous to 1/C , which makes sense, because with a given current for a given time, a smaller capacitor will build up more voltage, whereas with...

Sorry, what additional information should i provide?

Homework Statement Suppose we have spring which is between two bodies of different mass, with which force spring will act on every of them? Homework Equations Spring acts on a body with force kx The Attempt at a Solution A-/\/\/\/\/\/\/\-B Suppose body A has mass 2kg and body B has mass...

Homework Statement Why integration of $$\frac{D^2\mathbf r}{Dt^2}=−2\mathbf w \times \frac{D\mathbf r}{Dt}−g\mathbf R$$ gives us $$\frac{D\mathbf r}{Dt}= \mathbf v_0 −2\mathbf w×(\mathbf r−\mathbf r_0)−gt\mathbf R$$ Homework Equations Consider a time-varying vector written in the body...

Homework Statement While reading course lecture at ocw.mit i have stumpled upon such an equation $$\dot H_O = \sum_{i=1}^n (\dot r_i \times m_i v_i) + \sum_{i=1}^n (r_i \times m_i \dot v_i) = 0 + \sum_{i=1}^n (r_i \times (F_i + \sum_{j=1, j\ne i}f_{ij} )) = \sum_{i=1}^n (r_i \times Fi) +...

Thank you for the reply. But we have shear stress in the middle of bar side. The problem for me is that regarding edges the author says that surface is free and he concludes from it that shear stresses are zeros there. But why then surface is not free in the middle of bar side? Certainly, the...

Now I'm reading part THIN-WALLED HOLLOW SHAFTS The book says this We now detach a small element from the wall portion AB (Fig. 201 3.50). Since the upper and lower faces of this element are part of the free surface of the hollow member, the stresses on these faces are equal to zero. Why its...

Yeh, the books tells the same about the position of the maximum shear stress. It says about free surface only for the edges.

I'm currently reading Beer MoM book. There is nothing new for me in this tutorial. I'm particulary like to understand this passage: Since the face of the element perpendicular to the y-axis is part of the free surface of the bar, all stresses on this face must be zero.

Homework Statement I want to understand why in noncicular members in torsion book tells me that surface of a member is free and so no shearing stresses there. This is from wikipedia for shafts: Note that the highest shear stress occurs on the surface of the shaft, where the radius is...

The rule to convert between frames is multiply by rotation matrix. But here we add some term, which is strange for me. I can very well understand this in case of measuring angular momentum about different points... Oooo, maybe here they think of different frames also as diferent points to...

Suppose we have an equation in inertial frame A. \begin{equation}\frac{{}^Ad\bf{H}_C}{dt} = \bf{M}_C\end{equation} Now we want to switch to body fixed frame B. For this need to employ correction factor {}^A\bf\omega^B\times\bf{H}_B. Why do we have this correction factor? How to derive this...

Sorry, could you please use itex tag, it is hard to understand your equations. Thanks.

So, x = r*theta and y = r.