Why is Newtonian mechanics still taught when it's wrong?

>why is 3.14 used for pi when it's wrong

>>8045502
It's not wrong, it's inaccurate in a way that is irrelevant for the set of problems it's used in, Newtonian mechanics is still used in many papers.

Because it is valid for most things we encounter in everyday life.

>Physics (also known as "natural philosophy") is the analysis of nature that is conducted in order to [math] \underline{ model } [/math] phenomena to describe how the universe behaves and gain partial understanding of it. One must keep in mind that physical laws and theories are never [math] proven [/math] nor [math] refuted [/math] but examined on how well they are in agreement to observations and in what domain of physical parameters (speed, temperature, pressure, field strength, etc) they remain in acceptable agreement with experimental observations. While it may be very temping to assume our equations are the unbreakable rules or source code of the universe, we must realize that such absolute knowledge is fundamentally and hopelessly unknowable.

>>8045502
Same reason we don't calculate our exact gravitational acceleration based on our altitude when 9.8m/s/s will do. It's a good approximation and that's enough.

>>8045534
Its fundamentally incorrect though...

>>8045502
Why is water analogies used for electricity when it is wrong?

>>8046062
So is relativity and quantum mechanics, if you want to be pedantic.

>>8046062
>fundamentally incorrect

What do you mean by this? Real life is not exact and therefore we must result to models that best approximate it. Newtonian mechanics (and by extension, Lagrangian/Hamiltonian mechanics) may not be EXACT but they are extremely good approximations. Want something more precise? Apply pertubation theory to your mechanics; it will still not be exact but it will at least be the most approximate solution to your problem.

>>8045502
Because it works very well in certain circumstances. And these circumstances happen to be the most relevant circumstances for people's every day life. Sometimes an easily done approximation is better than a very precise but annoying time-consuming solution.

>>8045502
autism

File: 1456203547106.gif (3MB, 320x240px) Image search: [Google]

3MB, 320x240px

>>8045502
it just werks

>>8046102
I tutor for applied electrical kids and have tried to demonstrate the water analogy and a "balls" analogy that's way closer to the way electrons work. They imagine that the conductor is a pipe and current is the number of balls passing through a part of the conductor a second. Voltage is how hard the balls are being pushed through the pipe, and resistance is either a smaller area of the pipe so the balls have to really press through there (which works because if your resistance is higher your current is less I = V / R, so there's less balls passing through quickly). This helps prevent a lot of confusion later and the kids get it WAY quicker

>I'm pretty sure there was no reason to make this post but some autism kicked in and I felt like it

>>8046648
You seem to enjoy talking about balls.

>>8046648
Definitely a lot better than the water analogy

>>8045502
Because [eqn] t' = \gamma \left ( t - \frac { vx } { c^2 } \right ) \approx t ~ \text { when } ~ v << c [/eqn] And [eqn] x' = \gamma \left ( x - vt \right ) \approx x - vt ~ \text { when } ~ v << c [/eqn] What I'm trying to say is that classical mechanics isn't wrong, but it's a great approximation for sufficiently slow velocities.

>>8045502
Are you genuinely curious or are you just being a semantic asshole?

>>8046958
I'm genuinely curious

>>8045523
It is wrong, but it's a good approximation in a bunch of cases.

>>8046106
How do you know?

>>8046116
>real life is not exact
What does this even mean?

>>8046696
That's what electrical engineering does

>>8046116

I'm not fully disagreeing with you, just saying.

>Real life is not exact
Yes it is. Our observations and measurements are not, but the real physical world is exact. Think about it, it has to be exact because that is the exact thing we are trying to measure. What ever the measure is, it is always correct and exact.

Also, if at the quantum level physics is quantized, we may eventually be able to make precise measurements.

>>8047169
>the real physical world is exact
>it has to be exact
>it is always correct and exact
go home Aristotle, you're drunk

>>8045502
>>fuckingeveryone
http://hermiene.net/essays-trans/relativity_of_wrong.html

>>8045502
Because its a useful approximation for earthly objects on the human scale.

>>8046116
>>8046992
dark matter and dark energy are the obvious hint that current theory is incorrect.

>>8047169
I imagine that it works just like evolution. It is not exact, but the impurities are slowly disappearing.

>>8047224
>>8047252

*measuring the object*
Hmm, results don't add up!
Conclusion: reality must be wrong.

>>8046992
How do you know that Newtonian mechanics is "incorrect"? Answer: you don't, or you wouldn't be asking such questions.

Why is psychology still taught when it's wrong?

>>8047402
Lets stay on topic here

This is about the Newtonian view of things