this post was submitted on 14 Jul 2023
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[–] [email protected] -1 points 1 year ago (2 children)

Not in real life though. Only in Highschool physics class.

[–] [email protected] 0 points 1 year ago* (last edited 1 year ago) (1 children)

That's because of friction and air resistance which are still forces. Repeat the same experiment in outer space where there's no atmosphere or stuff in the way and you won't see that

There's even things like ion engines that take advantage of that by producing tiny amounts of thrust but run over long amounts of time to build up quite a bit of speed

https://en.m.wikipedia.org/wiki/Ion_thruster

[–] [email protected] -1 points 1 year ago* (last edited 1 year ago)

Having taken not only Highschool physics but also university physics courses I know that.

That doesn’t change that for most people in most environments the sentence “if an object isn’t pushed it’ll stop” is, in fact, true.

It becomes false only if you change the context, but I would argue, if you know all the facts and scenarios, that’s willful misunderstanding.

[–] [email protected] 0 points 1 year ago (1 children)

Physics is about nothing but real life

[–] [email protected] -1 points 1 year ago* (last edited 1 year ago) (2 children)

A statement so general that it is useless.high school physics does so many simplifications that it’s only about very specific experiments in real life, but is generally not very accurate.

[–] [email protected] 1 points 1 year ago

Statistical approximations are a large part of complex systems, such as the summation of billions of forces of atoms.

Id argue given the insane ammount of moving parts, a simplication as easy to understand as Newtonian mechanics is extremely accurate, at least compared to the limited input data

[–] [email protected] 0 points 1 year ago (1 children)

As a high school physics teacher, if this is the hill you're willing to die on, then you neither understood the content in your high school physics class nor your university physics class. Newton's 2nd law is generally accurate in most scenarios even without simplifications.

[–] [email protected] -1 points 1 year ago (1 children)

Like me stopping to peddle my bike?

[–] [email protected] 1 points 1 year ago* (last edited 1 year ago)

Yes, like you stopping to peddle your bike...

A simple force diagram and application of newton's 2nd law predicts the bike should accelerate to the left while it's velocity is towards the right. This means the bike should slow down.