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Started programming on a ZX spectrum in the 80's and have moved through Assembly, Turbo Pascal, C++, C#, Fortran. My main area of focus is engineering and scientific computing like numerical methods and 3D graphics.


Oct
26
comment Rotational Inertia of Two rods
What is $h$? The figure shows $d$ for distances.
Oct
26
comment Sum of energy from torques of several disks in double rotation
What drives the disks?
Oct
23
comment what make the bottom portion of a wheel in rolling motion move?
Here we are talking about the concept of instantaneous speed. The bottom at any instant does not move, but the next instant is not at the bottom any more.
Oct
23
comment Hooks Law and acceleration
So what is your question?
Oct
23
comment Is a double integral required to find the moment of Inertia of a non-uniform sphere?
Also see hyperphysics.phy-astr.gsu.edu/hbase/isph.html
Oct
23
comment Is a double integral required to find the moment of Inertia of a non-uniform sphere?
You can use a single integral if you consider multiple shells, like an onion.
Oct
22
answered What is the relationship between force and momentum in collisions?
Oct
22
comment Does a tire need to slip to generate force?
Notice that car handling is most influenced by the reaction moments produced by lateral forces. Those make the reaction center of the tire patch be behind the centroid of the patch such that the tire tracks (centers) as it rolls.
Oct
19
comment Underdetermined forces in a statics problem
Interesting question that relates to the painleve problem.
Oct
19
comment Underdetermined forces in a statics problem
If the angle was less than the critical angle then the reaction would be within the friction cone and the problem would be undetermined. As it stands now the problem is deterministic since you can safely assume micro slipping in the interface with $F = \mu N$ exactly. That is if $\mu<1$.
Oct
18
comment Why do white dwarfs shine white?
I learned that the sun from space appears white. So a white dwarf with the same outer temperature will appear the same color.
Oct
16
revised Rolling a ball into a cone; what should the forces overall be?
added 240 characters in body
Oct
16
comment Rolling a ball into a cone; what should the forces overall be?
To consider the rotational inertia complicates the equations because the only thing providing a torque is friction. My background is in robotics and dynamics.
Oct
15
comment Angular displacement after full rotation
You need to provide more context here. At least a reference or something. Besides the obvious displacement = n × 360°.
Oct
15
revised Rolling a ball into a cone; what should the forces overall be?
added 229 characters in body
Oct
15
answered Rolling a ball into a cone; what should the forces overall be?
Oct
15
comment Rolling a ball into a cone; what should the forces overall be?
@julianfernandez If you assume pure rolling always, the friction coefficient should cancel out and equations should simplify. Please show your work for the community.
Oct
15
comment Tensorial version of Hooke's law
Your forces usually come from statics or dynamics. They are transformed into stresses and then strains to be re-transformed into deflections. In the end you have your stiffness matrix.
Oct
15
comment Tensorial version of Hooke's law
Did you read Wikipedia on isotropic materials fully? Also look at en.wikipedia.org/wiki/Linear_elasticity
Oct
15
comment Tensorial version of Hooke's law
Is there a particular example you are working with? The answer is geometry dependent.