Recent content by ptd-

Thank you! clear as day now.

Perhaps I might rephrase my previous post. Wouldn't the immediate 3-d analog to the projection of a line segment in 2-d space onto an axis (essentially the dot product with a unit vector along the axis) simply be the dot product of a line in 3-d space (i.e. a vector in 3-d) onto another...

I understand the length ratio of the projection of a line onto an axis is the direction cosine (cos of angle between line and the axis). In fact for this case, the unit normal vector to the plane has a projected length nx along the x-axis. I just don't see how that logic extends to these...

This problem refers specifically to http://books.google.com/books?id=W9ZuLZWldUoC&lpg=PA9&ots=2lrfqlB3j7&dq=%22stress%20components%20on%20an%20arbitrary%20plane%22&pg=PA10#v=onepage&q=%22stress%20components%20on%20an%20arbitrary%20plane%22&f=false". The text comments that Area BOC =...

Thanks for your replies. I believe the text boxes are inconsistent because they will give a different answer for average impact force. For example, plug in m = 1 kg, h = 1 m, d = 1 m. Diazona's equation would yield a value of 19.6 N, whereas text boxes 9.8 N. Edit: it's actually...

http://hyperphysics.phy-astr.gsu.edu/hbase/flobi.html" Since the gravitational potential energy of the falling object at the point of impact is higher than the gravitational potential energy at the distance traveled after impact, where does the energy go? It is shown that the KE is removed...