Physics
>
GCSE
>
Newton's Laws
>
Were Newto...
2 years ago
·
43 Replies
·
6180 views
Kara Johnston
43 Answers
Newton's laws are still used today because they more or less work fine. We used Newton's laws to go to the moon. However when travelling at any appreciable speed and when accuracy is paramount (think GPS satellites) Special Relativity is used to make more accurate calculations.
No, Newton's Laws of Motion are still valid.
Physics teacher (Enhanced DBS certified),13 years experience
NO, they are the basics on which quantum mechanics is based. In quantum mechanics, we discuss the particles at micro scale where Newtonian mechanics failed to explain those concepts. but at macro level, it works perfectly well.
I'm available for 1:1 private online tuition!
Click here to view my profile and arrange a free introduction.No. Newton's laws are derterministic for objects in space-time that operate in everyday life. However, Quantum Mechanics describes the unseen world. It seems absurd that QM in principle, superseeds Newton's laws but, if one digs deeper, QM does make use of Newton's Laws or Newtonion Mechanics when they are 'Generalized'. Some examples are Hamiltonion, Lagrangian, and Routhinian Mechanics. Hope this answers your question.
No. Newton's laws are used to explain our daily life while at the atomic level, they fail to explain the motion and nature of atoms and that is where quantum mechanics come in. Therefore, Newton's laws are still in use.
No they weren’t, Newtonian mechanics are very useful and accurate on the scales we work with generally in day to day life, Quantum mechanics on these scales produce the same answers as Newtonian mechanics, we only see large disparities between the two at the ~atomic scale
Quantum mechanics do violate newtons laws, spesiffically his first law. However, quantum mechanics hasn't nessacarily 'superseded' newtons laws as quantum mechanics essentially describes different scales than what newtons laws describe. Newtons laws describe earthy mechanics (things that we may see and experience) quantum mechanics on the other hand deals with the extremely small, mostly they do not adress the same problems. Something that could be said to have superseded Newtons laws is relativity, (get in contact with me for a conversation about that).
"to infinity and beyond!"
Good question, the answer is no, they weren't superseded, because the two describe different regimes.
Newton's Laws pertain to something called 'classical physics', which works with the macroscopic (large scale) going-ons of the macroscopic world. Classical physics is 'deterministic' (a.k.a, you can measure things and get concrete answers, like knowing both the position and speed of a car on the motorway, for instance.)
However, when applied to calculations concerning the quantum world - the scale of atoms and below - Newton's laws fail to correctly predict things.
Quantum mechanics (QM) is the study of quantum objects and is a theory that explains things on that scale with exquisite precision. However, because of the speeds at which some quantum objects are travelling, QM says one cannot know, with infinite precision, both the position and speed of an object. This statistical nature is what differentiates it from the absolute deterministic nature of our familiar classical world.
To surmise:
classical mechanics says: 'the car's travelling this fast and here it is.'
quantum mechanics says: 'this electron is more likely here than there, and it's more likely travelling faster than slower.'
For the moment, Classical Physics and Quantum Physics stand apart, divorced, because no one yet knows how to blend the two into one theory. This is one of physics frontier questions, (and if you solve it, you'll be rich!) so for the moment, we just use the two separately.
I'm available for 1:1 private online tuition!
Click here to view my profile and arrange a free introduction.No it doesn’t but in a miscroscopic word it does
when the energy is little or the masses are small
Quantum mechanics never set newtons law incorrect
The answer is both yes and no! Newton's laws concern physics on large scales (in comparison to an atom) and so isn't truly in the realm of quantum mechanics which deals with physics on the smallest of scales. Newton's laws were in fact superseded by Einstein's theory of general relativity which deals with phenomena on the largest of scales
Newton's Laws are inapplicable in atomic and subatomic scales, due to the added consideration of strong, weak and electromagnetic forces. So ultimately, at a larger scale, Newton's Laws are applicable, however on the quantum scale they aren't.
Friendly and patient tutor with a passion for technical subjects
Newton's laws remain a valid approximation that work well in everyday situations. We can still safely use our three laws of motion when doing problems about things like the motion of cars on the road.
Einstein's theory of relativity provides a more complete framework that takes into account the behaviour of objects as they approach the speed of light, and is needed for understanding how astronomical phenomena like black holes work.
Quantum mechanics provides insight into the behaviour of matter on a very small scale, and does in some sense supersede Newton's laws for the behaviour of atoms and other particles. We can't really treat atoms like billiard balls that simply bounce off each other - at a quantum scale things are different and more 'fuzzy'.
I'm available for 1:1 private online tuition!
Click here to view my profile and arrange a free introduction.Enthusiastic physics and maths tutor with 31 years experience
89 reviews
Not really. In terms of A-level Newton's Laws are fully correct for macroscopic objects-even those requiring a microscope to see-i.e persons, planets, vehicles, tiny oil drops etc. Quantum physics only applies to subatomic particles. Additionally, subatomic particles conserve momentum in the Newtonian was...
I'm available for 1:1 private online tuition!
Click here to view my profile and arrange a free introduction.Hi Kara,
This is an interesting question. Maybe trying to reframe it would make you understand it better. You can think of Mechanics as a subfield of Physics, it deals primarily with static or moving bodies inserted into a certain space. Newton's Laws of Mechanics apply in a specific area of this subfield, that of the visible world, anything from an ant to a jet will comply to Newton's equations just fine with little to no error.
However, when we move our observed space into smaller or bigger objects, these equations, while still somewhat valid, start to break apart and return wrong results when measured experimentally. That is where quantum mechanics comes in. The equations that Dirac, Plank, among others developed, work very well for objects inside this size scale, for example an atom can have a radius of 0.1 nanometers (that's 10000000000 times smaller than a meter!), here quantum mechanics works perfectly.
Now, for an extra thought, if we go to a large scale, a whole planet for example, General and Special relativity become the standard Mechanical equations we deal with. While Newton's equations work relatively better than for quantum scales, it still does not account for many phenomena we observe with objects so massive.
TL;DR It is not a matter of superseding one another, these theories complement each other to provide a complete view of our universe and the phenomena around us. As Newton famously said “If I have seen further it is by standing on the shoulders of Giants".
Not necessarily. However quantum mechanics provided clarity to lots of unanswered questions regarding mechanics at the atomic level. Classical/Newtonian mechanics failed to provide answers to certain questions surrounding black body radiation and energy levels in atoms.
Quantum mechanics therefore provided us a more accurate insight into the world of subatomic particles addressing the limitations of Newtonian mechanics.
Think you can help?
Get started with a free online introductions with an experienced and qualified online tutor on Sherpa.
Find a GCSE Physics Tutor