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location United States
age 44
visits member for 4 years, 9 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. #SOreadytohelp


Aug
13
comment Cinema and TV pictures
Did you google how a TV works?
Aug
13
answered Pulley system: how can tensions be equal throughout a entire rope if the weights on opposite ends are different?
Aug
13
revised Is it true that light has a lot of energy but cannot exert force
added 10 characters in body
Aug
13
awarded  forces
Aug
12
comment What are the limitations of using instantaneous axis of rotation?
That, plus the parallel translation which is not included in Euler's theorem. Rotation is the $\vec{r}\times \vec{e}$ part and translation the $h \vec{e}$ part of any linear velocity vector.
Aug
11
answered What are the limitations of using instantaneous axis of rotation?
Aug
11
comment What are the limitations of using instantaneous axis of rotation?
There is always an instantaneous axis of rotation defined. You heard wrong.
Aug
11
comment Convert an equation for acceleration into one for velocity
possible duplicate of How to get distance when acceleration is not constant?
Aug
11
comment Resultant center of rotation due to multiple moments
You can with force. You can't with moment only. When a body rotates about a pin under the influence of a moment, it is the reaction forces of the pin that move the center of mass.
Aug
11
revised Resultant center of rotation due to multiple moments
added 837 characters in body
Aug
11
answered Resultant center of rotation due to multiple moments
Aug
11
comment Resultant center of rotation due to multiple moments
@KyleKanos because an electric drill does not produce a pure moment. In fact it is quite difficult to produce a pure moment without a net force.
Aug
9
answered Which moment of intertia do I need to calculate torque
Aug
8
comment Which moment of intertia do I need to calculate torque
Does the pivot axis pass through the center of mass ?
Aug
8
comment Can photons accelerate?
Maybe, but transverse acceleration has units of $m/s^2$ and angular acceleration of $rad/s^2$.
Aug
7
comment the final velocity non-constant acceleration
See physics.stackexchange.com/a/15620/392 for the math of calculating motion with non-constant acceleration. In your case the acceleration is a function of distance, so $$\frac{1}{2} v^2 = \int a \,{\rm d} x$$
Aug
7
comment Can photons accelerate?
Transverse acceleration is acceleration perpendicular to the direction of motion causing the path to curve. It is equal to $\frac{c^2}{r}$ where $r$ is the radius of curvature.
Aug
7
comment Can photons accelerate?
Wouldn't that be transverse acceleration and not angular acceleration?
Aug
7
comment Force needed to deflect a gyro
You know that $$\frac{{\rm d}\vec{L}}{{\rm d}t} = I \dot{\vec{\omega}} + \vec{\omega} \times I \vec{\omega}$$ since the mass moment of inertia changes with orientation.
Aug
7
comment Can photons accelerate?
Photons slow down when entering dense media. So they must accelerate afterwards when they leave.