Chronology Current Month Current Thread Current Date
[Year List] [Month List (current year)] [Date Index] [Thread Index] [Thread Prev] [Thread Next] [Date Prev] [Date Next]

Re: Flashlight

In a private message XXX wrote:

In general, I always appreciate a written explanation before
the formula is given to show the mathematical relationship.
For example, in paragraph 5 where power is introduced, why
is power the product of potential difference and current? Is
there an analogy to mechanics or fluid dynamics that might
help here? I can memorize the formula if I need to but I would
much rather understand why the relationship exists. Then I can
derive the formula whenever I need it and will be more likely
to remember it.

The first formula which came to my mind was P=F*v. But is
it really a good analogy for the P=U*I ? Probably not. What
would be a better analogy, at the level of my description?

Power is the rate at which another "invisible fluid", energy,
is being converted from one form to another. How to make
this clear without "borrowing from what we will learn later?"

Ludwik Kowalski wrote:

As a pedagogical exercise I plan to create several short essays on basic ideas
of electricity and magnetism. The draft of the first item is on my web site at:

http://alpha.montclair.edu/~kowalskiL/electr/flash.html

Critical comments and suggestions will be appreciated, either openly or in
private. The paragraphs have been numbered to facilitate comments.

Ludwik KowalskiL ---> kowalskiL@mail.montclair.edu