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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.


Aug
10
comment Planck time, time or time interval?
possible duplicate of Is time continuous?
Aug
9
comment Kinematics problem involving rocket
For the first stage acceleration is $20 {\rm nm/s}$ and for the second stage it is $-g$. Now integrate the acceleration to get velocity and height.
Aug
9
comment Applying a force on a rigid body which is used to create torque
Yes to find the static equilibrium you set $\sum \vec{F} =0$ and $\sum \vec{\tau}=0$ and solve for three (in 2D problems) components like $F_{2y}$ and the two reactions at the pivot point (red circle).
Aug
9
revised Applying a force on a rigid body which is used to create torque
added 363 characters in body
Aug
9
answered Applying a force on a rigid body which is used to create torque
Aug
9
comment Applying a force on a rigid body which is used to create torque
You need to provide the direction of $F_1$ to correctly calculate torque.
Aug
8
comment How to get rotational speed after disk-disk collision with friction?
Other relevant work as it relates to simulations (and game development) found here graphics.stanford.edu/courses/cs468-03-winter/Papers/ibsrb.pdf
Aug
8
comment How to get rotational speed after disk-disk collision with friction?
This is a reasonable problem that leads to the treatment of frictional forces as impulses. See ruina.tam.cornell.edu/research/topics/collision_mechanics/…
Aug
8
answered Is there any relation between Planck constant and Gravitational constant?
Aug
8
comment Force and torque on rigid body in space
You are correct. And if the radius is $r$ there is a point the body is rotating about located a distance $\frac{I}{m r}$ distance from the center. This is the instant center of rotation. Now if you apply the force at the instant center of rotation, the disk will appear to "roll" about it's edge.
Aug
8
revised Torque definition and right hand rule not arbitrary
added 162 characters in body
Aug
8
answered Torque definition and right hand rule not arbitrary
Aug
8
comment Torque definition and right hand rule not arbitrary
$\tau_{yx}$ means torque about the $z$ axis and it is a horrible way of representing in since $\tau_{yx} = \tau_{xy} = \tau_{z}$ and torques are vectors and not tensors. Actually a torque is the position dependent component of the force screw.
Aug
8
comment Torque definition and right hand rule not arbitrary
Who does torques by component. The definition is $\vec{\tau} = \vec{r} \times \vec{F}$ in vector form.
Aug
7
answered Coupled Spring System (3 mass 3 springs)
Aug
7
comment Why can't light penetrate solid objects?
I heard that if you compress aluminum (or aluminium) enough it turns transparent.
Aug
6
comment How to approximate acceleration from a trajectory's coordinates?
This assumes a constant acceleration over 3 sample points, which usually does not hold. It is better to do a higher order slope estimate, like with cubic splines.
Aug
6
answered How to approximate acceleration from a trajectory's coordinates?
Aug
6
comment How to approximate acceleration from a trajectory's coordinates?
For acceleration you need speed and curvature. The curvature you get by the path, but for speed you need time information. (related: physics.stackexchange.com/a/127967/392)
Aug
4
comment Finding direction of a ball after collision in cartesian coordinate system
This question appears to be off-topic because the solution can be found in en.wikipedia.org/wiki/…