Can High School Physics Teachers Teach Non-Empirical Concepts?

[physdoc]

Are high school physics teachers only allowed to teach physics that is strictly empirical?

 

[cjl]

Why would they be limited to that?

 

[jtbell]

physics that is strictly empirical?

What do you consider to be "physics that is not strictly empirical"?

 

[physdoc]

Why would they be limited to that?

well... aren't they only supposed to teach real science and, isn't real science only empirical? How could something be science and not be empirical?

 

[physdoc]

What do you consider to be "physics that is not strictly empirical"?

...for example, the vis viva equation, that an object's energy is equal to mass multiplied by the square of its velocity

 

[brainpushups]

for example, the vis viva equation, that an object's energy is equal to mass multiplied by the square of its velocity

If you are saying that vis viva is not empirically based you would be mistaken. Leibniz cited Galileo's experiments on the relationship between speed and height to formulate his notion of vis viva. Can you give a different example or explain yourself further?

 

[physdoc]

In this sense vis viva is empirically based, since energy is proportional to mass multiplied by velocity squared, but not equal to it. KE = 1/2MV^2; here, an object set into motion with twice the velocity will move a distance four times as great, with three times the velocity, nine times as great. This is makes energy proportional to MV^2, not equal to it, although it is equal to 1/2 this.

 

[Dr. Courtney]

High school physics teachers usually have fairly broad latitude, because at most high schools (at least in the US), there is no one else on the faculty who knows enough physics to delve into the distinctions you are trying to make.

If the students are doing well enough on the standardized tests, a physics teacher is unlikely to get any grief for throwing in a couple of non-standard topics unless they are religious or something.

 

[physdoc]

The post I just wrote about the distinction between KE being proportional and not equal to MV^2 is valid and could actually have been included in the curriculum without any wrongdoing or inaccuracy on the part of the teacher. I wasn't clear on exactly what I meant on weather or not only empirical ideas are taught in the physics classroom. My example with vis viva was put forth because work = KE = 1/2MV^2. If the teacher said that work = 2 x the KE, then this would not be empirical? But forget about that. I just tried an example. Please answer my original question. Are only empirical ideas allowed to be taught in the physics classroom. The reason I brought up vis viva is because if it is taught that the work required to set a body in motion is equal to 2 x its KE, then this would not be empirical, because it cannot be tested.

 

[physdoc]

On the other hand, it is indeed a small distinction regarding "proportional" or "equal to", but if the teacher stated that work was equal to MV^2, this would not be empirical, no?

 

[physdoc]

Empirical means something that can be observed and tested and verified as fact. How can we experimentally verify that work is equal to MV^2? KE on the other hand can be verified, because we know that the resistance that can be overcome by a body in motion is = KE = 1/2MV^2

 

[physdoc]

To be exact, it is not a small distinction regarding "proportional to" or "equal to".

 

[physdoc]

High school physics teachers usually have fairly broad latitude, because at most high schools (at least in the US), there is no one else on the faculty who knows enough physics to delve into the distinctions you are trying to make.

If the students are doing well enough on the standardized tests, a physics teacher is unlikely to get any grief for throwing in a couple of non-standard topics unless they are religious or something.

non-standard doesn't make something empirical or not

 

[brainpushups]

In this sense vis viva is empirically based, since energy is proportional to mass multiplied by velocity squared, but not equal to it. KE = 1/2MV^2; here, an object set into motion with twice the velocity will move a distance four times as great, with three times the velocity, nine times as great. This is makes energy proportional to MV^2, not equal to it, although it is equal to 1/2 this.

But that choice is arbitrary and due to the units chosen for work. We could have defined kinetic energy to be equal to mv^2 and defined work as 2Fd. It was Coriolis' definition of work that added the factor of 1/2 to the vis viva term. It is perhaps important to keep in mind that the early pioneers of modern classical physics worked mostly with proportions and not with direct equations since algebra had not yet been fully developed.

But let's not get hung up on this example.

Empirical means something that can be observed and tested and verified as fact.

I'm sure there are topics broached by physics teachers at the high school level that do not meet this qualification. For example, I've had students give presentations on topics in modern physics. Any student that presents on string theory (if we want to call that physics) would be presenting a non-empirical theory by your definition (now, you could certainly argue that the teachers aren't 'teaching' string theory by doing this, but simply surveying the modern topics).

Interestingly, the 'atomic hypothesis' could have counted as a non-empirical theory before the technology was developed to 'see' atoms. Mach argued that the atomic hypothesis was not scientific because atoms could not be observed and thought that people shouldn't accept it.

Can we substitute 'metaphysical' for 'non-empirical' or do you think there is a distinction?

 

[brainpushups]

There is a distinction between 'metaphysical' and 'empirical', ...right?

I think you meant 'non-empirical.' I would not draw a distinction. Something non-empirical, by your definition above, would be the same as something metaphysical according to my understanding. I just wanted to make sure that you didn't have any objection before I proceeded further.

 

[physdoc]

But that choice is arbitrary and due to the units chosen for work. We could have defined kinetic energy to be equal to mv^2 and defined work as 2Fd. It was Coriolis' definition of work that added the factor of 1/2 to the vis viva term. It is perhaps important to keep in mind that the early pioneers of modern classical physics worked mostly with proportions and not with direct equations since algebra had not yet been fully developed.

But let's not get hung up on this example.
I'm sure there are topics broached by physics teachers at the high school level that do not meet this qualification. For example, I've had students give presentations on topics in modern physics. Any student that presents on string theory (if we want to call that physics) would be presenting a non-empirical theory by your definition (now, you could certainly argue that the teachers aren't 'teaching' string theory by doing this, but simply surveying the modern topics).

Interestingly, the 'atomic hypothesis' could have counted as a non-empirical theory before the technology was developed to 'see' atoms. Mach argued that the atomic hypothesis was not scientific because atoms could not be observed and thought that people shouldn't accept it.

Can we substitute 'metaphysical' for 'non-empirical' or do you think there is a distinction?

what is the definition of metaphysical?

 

[physdoc]

My teacher always taught us that KE or Work = 1/2MV^2, not MV^2

 

[physdoc]

My teacher always taught us that KE or Work = 1/2MV^2, not MV^2

But there was a time, looking back when he seemed to be (just from a fragment of what he said, as this is all I remember) talking about MV^2, or twice the work. The fragment was exactly this: there was picture of a parabola on the board in lab or pre-lab in which he was marking off points and saying (and writing at the same time) "1/2"..."1/2"..."1/2", and crossing each one half off before he proceeded to writing the next one half. What was this. Do you remember your physics teacher doing something like this?

 

[brainpushups]

Well, metaphysics is a broad category of philosophy dealing with many different things. Like physics, metaphysics is concerned with the fundamental parts of nature and the rules (usually non-mathematical) that govern them. It is inherently non-testable. For example, a classic metaphysical principle is that the planets move in circular motions because circles are the most perfect shape. Another more modern metaphysical principle is Maupertuis' principle of least action which claims that nature is economical in its processes.

My teacher always taught us that KE or Work = 1/2MV^2, not MV^2

Sure, I'm not disputing that; it is the best way to define that quantity because it gets rid of many 'extra' factors of 2 that would appear if the units were chosen differently. My point was that this choice was arbitrary.

 

[physdoc]

But there was a time, looking back when he seemed to be (just from a fragment of what he said, as this is all I remember) talking about MV^2, or twice the work. The fragment was exactly this: there was picture of a parabola on the board in lab or pre-lab in which he was marking off points and saying (and writing at the same time) "1/2"..."1/2"..."1/2", and crossing each one half off before he proceeded to writing the next one half. What was this. Do you remember your physics teacher doing something like this?

this was before the midterm

 

[brainpushups]

What was this. Do you remember your physics teacher doing something like this?

I'd need more information to interpret what he was doing.

 

[physdoc]

Well, metaphysics is a broad category of philosophy dealing with many different things. Like physics, metaphysics is concerned with the fundamental parts of nature and the rules (usually non-mathematical) that govern them. It is inherently non-testable. For example, a classic metaphysical principle is that the planets move in circular motions because circles are the most perfect shape. Another more modern metaphysical principle is Maupertuis' principle of least action which claims that nature is economical in its processes. Sure, I'm not disputing that; it is the best way to define that quantity because it gets rid of many 'extra' factors of 2 that would appear if the units were chosen differently. My point was that this choice was arbitrary.

I think it's arbitrary too.

 

[physdoc]

I'd need more information to interpret what he was doing.

I've been trying to figure it out for the longest time.

 

[physdoc]

Did your physics teacher ever define work or KE as MV^2 as opposed to 1/2MV^2?

 

[physdoc]

and how was the factor of "2" treated by men of science when thinking in terms of twice the KE or twice the work?

 

[Dr. Courtney]

non-standard doesn't make something empirical or not

But the debate here is so far off into the weeds that most high school administrators who might tell the teacher to stop won't understand the distinction, much less care enough about it to tell the teacher to stop.

I've worked with a lot of faculty through the years who have weird pet theories or alternate views that they enjoy spending a small amount of class time on over the course of the semester or year. If their students are otherwise learning the Physics they need to know, no one has ever been inclined to tell them to stop. Most high schools in the US only have 1 or 2 Physics teachers. It's not like there is a knowledgeable administrator to appreciate the distinctions and set boundaries.

But zooming out more broadly to high school science in general, I know there are a lot of things that are discussed as hypotheses. By definition, hypotheses are somewhat lacking in empirical support, yet I wouldn't fault a biology class for spending some time discussing the RNA world hypothesis or an Earth science class for spending time talking about the nebular hypothesis.

The ether was a non-empirical hypothesis in Physics that still receives (in my opinion) a disproportional amount of (favorable) discussion in some high school Physics classes. But I think this should be permissible as academic freedom.

 

[brainpushups]

and how was the factor of "2" treated by men of science when thinking in terms of twice the KE or twice the work?

Leibniz, for example, didn't have a concept of what we now call work. His argument for vis viva being the conserved quantity relied on the fact that the height reached by an object was proportional to the square of its speed; the factor of 2 didn't pop up because he only considered proportions.

I'm not positive about how those who came after the development of dynamics but before the development of work dealt with the factor of 2, but I think I remember seeing in some of Euler's work that there were '2s' all over the place because he was using vis viva. You can look on the Euler Archive at the relevant papers if you are interested. I have not read Lagrange's Analytical Mechanics so I'm not sure how he did it, but I expect it would be similar to Euler.

 

[Mister T]

This is makes energy proportional to MV^2, not equal to it, although it is equal to 1/2 this.

The factor of $\frac{1}{2}$ is convention. Discussing that, and things like it, are excellent ways to make the point that science is a creation of the human intellect. An act of imagination. What I mean by that is expressions like $\frac{1}{2}mv^2$ are not things that are discovered like a fossil is discovered buried under earth. Students need to understand that, in my opinion.

 

[physdoc]

The factor of $\frac{1}{2}$ is convention. Discussing that, and things like it, are excellent ways to make the point that science is a creation of the human intellect. An act of imagination. What I mean by that is expressions like $\frac{1}{2}mv^2$ are not things that are discovered like a fossil is discovered buried under earth. Students need to understand that, in my opinion.

I agree. Are you a teacher? If you are then maybe you can tell me what my physics teacher was talking about, when he was writing 1/2 on the parabola, and crossing each one off before proceeding to writing the next 1/2. I mentioned this above.

 

[Mister T]

I agree. Are you a teacher? If you are then maybe you can tell me what my physics teacher was talking about, when he was writing 1/2 on the parabola, and crossing each one off before proceeding to writing the next 1/2. I mentioned this above.

I teach physics at a two-year college. Sorry, but based on your account of your recollection I cannot even guess what it might have been.