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visits member for 3 years, 5 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.


3h
comment How long does it take for an electric car to go from 0 to 60 mph?
Now that is funny!
22h
comment Can a force applied to a wheel find the fastest way of getting to the other side?
BTW look up stress waves.
1d
comment Moment of inertia of rotating particles in center of mass frame?
possible duplicate of How does this formula for calculating the "mass sum" in a collision translate to 3D?
1d
comment Moment of inertia of rotating particles in center of mass frame?
IF you want to do 3D rigid body collision it gets really complicated really fast.
1d
comment “Derivation” of the Heisenberg Uncertainty Principle
This derivation is not rigorous, it is just illustrative.
1d
comment “Derivation” of the Heisenberg Uncertainty Principle
There will be an $x$ where they are all in phase. Take the CGD of the wavelengths to find where this is. Can can than do a change of coordinates to that node and it wont change the equations, nor the outcome.
1d
comment How long does it take for an electric car to go from 0 to 60 mph?
Related answer physics.stackexchange.com/a/15620/392
1d
comment If the axis of rotation is fixed, is it ok to say clockwise torque?
In fact when you do statics, you start by counting up all the resulting torques as +CCW and -CW, so just saying clockwise automatically means a negative value. Only in statics though, because the sum of moments is the same regardless of the point of reference. In dynamics, you must choose torques about the center of mass, always.
2d
comment Lateral forces on earths surface
If the giant sphere was resting on a frictionless surface then it would appear as if it was spinning in place.
Apr
14
comment Coordinate System vs. Angular Properties vs. Centroid
Yes, 3D dynamics and kinematics are straight forward if you get all your ducks in a row, but there are a lot of ducks to account for.
Apr
14
comment $\psi^*$ if you have sine or cosine function
@JamalS is it? You can have $\sin(\hat{i}) = \hat{i} \left( \frac{\hat{e}}{2} - \frac{1}{2 \hat{e}} \right)$. I think the answer is it depends on what $x$ is.
Apr
14
comment $\psi^*$ if you have sine or cosine function
I think this is valid question for Mathematics. "What is the complex conjugate of a sine function?"
Apr
14
comment Coordinate System vs. Angular Properties vs. Centroid
See related post physics.stackexchange.com/a/95542/392 if interested in the subject.
Apr
14
comment How long does it take for an electric car to go from 0 to 60 mph?
@jumpjack you are doing something wrong then. It is time to create a new question with the above, and show your work.
Apr
12
comment Describing a motion of gyroscope with gimbal
What I am missing above is the torques at the joints which accelerate the gimbal. Their result goes into joint moments $$\vec{\tau} = \hat{i} \tau_1 + E_1 \hat{j} \tau_2 + E_2 \hat{k} \tau_3$$
Apr
11
comment How long does it take for an electric car to go from 0 to 60 mph?
You can get $x(v)=\int \frac{v}{a}\,{\rm d}v$, but you wont be able to invert it I think. Try it.
Apr
10
comment How long does it take for an electric car to go from 0 to 60 mph?
@jumpjack read the FAQ on homework type questions. No complete answers are not allowed.
Apr
9
comment How long does it take for an electric car to go from 0 to 60 mph?
I gave you the tools to do the work yourself. This is how this site works. As far as torque goes, no manufacturers give torque at engine/flywheel always.
Apr
9
comment How long does it take for an electric car to go from 0 to 60 mph?
See now? I have been telling you for days, that this is the correct way of doing it. In your case you may need simulate small speed increments and calculate time and distance from there. Kind of like an numerical ODE solver.
Apr
9
comment How long does it take for an electric car to go from 0 to 60 mph?
$E = P t$ is wrong since $P$ is not constant. It is $E = \int P dt$ stated correctly.