You’re WRONG about Newton’s Third Law of Motion
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- Опубліковано 20 січ 2020
- 3rd Law is complicated and Newton’s original language is an impediment to our understanding. In this video I propose alternative language and focus on the common pitfalls of 3rd Law
this is an underrated video
Thanks!
I think it is because we always need a CAUSE and an EFFECT when ever we think of things. I mean even the F= M*A even feels weird because it should be thought of A = F/M. When we think of a rocket , we never think "oh it is because the rocket is accelerating , it is cause a large force" instead of the other way around. The problem of wording is always a problem, and our concepts appear to be somewhat related to our concepts of the term but I do not blame the wording of Newton that much compared to the wording of pre-modern chemistry, e.g. Mercury, mars, venus, etc.
Nope! I blame Newton for writing in Latin!
It is true that we look for a cause wherever we see a perceived effect and we are often wrong. There is a cause in these cases and we call it 3rd law. BUT we explain it badly and so did Newton. I propose changes in our language to understand teach it better.
I split our equations into 3 main categories - causal, definitional, or relational - ua-cam.com/video/eKjmYlSpNwU/v-deo.html
When my science teacher back in the day explained newtons 3rd law, he did it in a similar manner as you do in this video because he also did not agree with the wording.
His examples were also much different, one of them was a guy getting shot by a .50 caliber rifle. My teacher liked using this example to explain the force of inertia since logically the brain has a hard time explaining why a small piece of metal the size of ones finger could send a full sized man flying backwards, and thus the inability for the brain to form a logical reason on its own, causes it to be much more open to the concept of inertia and makes it much easier to memorize it. That and the example is hard to forget itself due to the nature of it
Plus if the target person is pushed back so hard the shooter will be also. 3rd law and momentum conservation.
Yeah, I understand what you're saying, but I also don't think your wording is any better. The example of hitting the air for instance, and "same sized" is unclear. Maybe explaining the energy expended as part of the wording might be beneficial..? To teach someone "same sized" would cause some to think that a balloon full of oxygen hitting a balloon full of osmium (as long as they are same sized) should push apart at the same rate. If you used this "same sized", you'd be criticised based on using the term "size", at least in my opinion.
Nope. "same size opposite FORCE." Force is push or pull. It's NOT energy and it's not the effect
"2 objects always apply same size opposite FORCES to each other" is still the best.
Energy is a different quantity and it must not be confused with force.
AND the two balloons "push apart at the same rate" means you (and everyone else) are totally confusing cause and effect. The acceleration effect will be different even though the forces on the two balloons are same size and opposite.
It helps a lot if we get used to drawing free body diagrams and thinking of forces - we don't do that well.