Re: superposition

[Ludwik Kowalski <kowalskil@MAIL.MONTCLAIR.EDU>]

Another example: two electric batteries, B1 and B2, in series with a
small light bulb. Each battery alone produces very small "amount of
light."  But together they produce A which is much larger than A1+A2.
Most people have experience with flash light sources. They know that
one battery will produce much much less than 50% of light one gets from
the normal set of two batteries.
Ludwik Kowalski

On Wednesday, Feb 25, 2004, at 12:02 America/New_York, RAUBER, JOEL
wrote:

> A good non-linear example is intensity in interference and diffraction
> phenomena.
>
> Intensity at the central peak for two point sources:
>
> 1+1 = 4
>
> and of course the points of destructive interference provide the
> opposite
> case!
>
> I'm glad this came up, I follow an optics before E&M ordering, and we
> just
> started electric fields, it will be good to remind them of intensity
> being a
> "familiar" non-superposition situation.
>
> Joel R.
>
> | -----Original Message-----
> | From: Forum for Physics Educators [mailto:PHYS-L@lists.nau.edu] On
> Behalf
> | Of Edmiston, Mike
> | Sent: Wednesday, February 25, 2004 10:19 AM
> | To: PHYS-L@lists.nau.edu
> | Subject: Re: superposition
> |
> | Ludwik's heater example is good, but I wonder if students will have a
> | feel for it.  I think they will have even less feel for the magnetic
> | field example.  I am looking for examples of supression and synergism
> | that students will clearly understand.  I have used fake math and
> | biological examples because they understand these.
> |
> | Superposition
> | 2+2 = 4
> | try to lift something with one arm, then with both arms.  The two
> forces
> | just add.
> |
> | Synergism
> | 2+2 = 5
> | Take a barbiturate and drink alcohol and get more than you bargained
> | for.
> | Look with either eye alone, then together.  Gain depth perception.
> |
> | Suppression
> | 2+2 = 3
> | Take tetracycline for an infection at the same time as taking Tums
> | (calcium) for an upset stomach.  Tetracycline is ineffective because
> it
> | binds to calcium and is not absorbed into the bloodstream from the
> small
> | intestine.
> |
> | I like the idea of physics examples because I don't want students to
> | think that superposition is always the rule in physics.  But often,
> it
> | is.  Do people know of other examples beyond what Ludwik mentioned?
> | Does anyone have physics examples for synergism?
> |
> |
> |
> | Michael D. Edmiston, Ph.D.
> | Professor of Chemistry and Physics
> | Bluffton College
> | Bluffton, OH 45817
> | (419)-358-3270
> | edmiston@bluffton.edu