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visits member for 3 years, 8 months
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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.


9h
comment Deriving spring oscilation period
Aghh, you should use math formatting for better readability.
2d
comment Lifting frictional force and relative values for kinetic vs static friction
Related paper: ewp.rpi.edu/hartford/~ernesto/F2012/FWM/Papers/Childs-App3.pdf
2d
comment Doubt in collision
Note $F=m g$ ONLY applies to a static case. Here as the ball experiences acceleration it is dynamic with $F-m g = m a$
2d
comment Work done by a frictional force on a cylinder
I meant is there anything else pushing the cylinder besides friction?
2d
comment Work done by a frictional force on a cylinder
What is motivating the cylinder to move, and how?
Jul
25
comment Straight line on 8-axis
Does your space have 8 coordinates in the same space, or is it a two vector of four. Like $V = [\hat{v},\hat{u}]$ where $\hat{v}=(x_0,x_1,x_2,x_3)$ and similarly for $\hat{u}$? I say this because a line in 3D is represented by pluecker coordinates with 6 values, and I am trying to understand how this relates to your 8D space.
Jul
25
comment Straight line on 8-axis
Unless a line in 3D is an intersection of a 2D object defined in 3D space. The same way that a line in 2D can be defined as the intersection of a 3D plane.
Jul
25
comment Calculate water flow rate through orifice
It doesn't matter. Pick $f=1$ to start with and iterate from there.
Jul
24
comment Calculate water flow rate through orifice
Actually $\Delta P = \rho g h$ so $h_f = h$ actually. This is the driver (motive force) of the motion. What concerns me is the $L$ which the the length of the orifice. I am not sure it is defined here.
Jul
24
comment Is static friction an impulsive force?
Are you talking about the painleve paradox?
Jul
24
comment Is static friction an impulsive force?
On the other hand static friction (sticktion) is used to control velocity similarly to how contact impulses control relative motion.
Jul
23
comment How does friction and mass of the string influence the tension force?
If it is massless and there is no other connection then it will not vary. Only when additional loading enters the picture the tension will change. The 3rd law describes the direction of tension mostly. The 2nd law really is used to find its magnitude.
Jul
22
comment How does friction and mass of the string influence the tension force?
No tension is the force needed to keep the rope from moving if it is sliced at a location. That is why we say "the tension at the end, or the middle." So it can vary with location in order to keep the balance.
Jul
22
comment Why do people with bigger hands/wrists have bigger torque advantages in arm wrestling?
Two words "Lever Ratio". See where the muscle is attached relative to the fulcrum.
Jul
21
comment Calculate vertical distance using acceleration
Which the OP can eliminate if they follow the method outlined in my answer.
Jul
20
comment Why is the inertia ellipsoid of a higher symmetry than the rigid body?
It is a good answer indeed.
Jul
20
comment Calculate vertical distance using acceleration
Shouldn't the red line (position) go back to zero after the event?
Jul
20
comment Approximating Rolling/Sliding in 2D Shape
Some courses dealing with this subject ocw.uc3m.es/ingenieria-mecanica/machine-theory/lectures-1/…
Jul
20
comment Approximating Rolling/Sliding in 2D Shape
Look up cam and roller analysis, as well as cam kinematics. In your case the roller is really big (flat ground), but you should get an idea of how to handle these problems.
Jul
18
comment How are the distances to the most distant $\gamma$-ray bursts measured?
possible duplicate of How do you measure distance to stars within the galaxy?