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Hey, Marty--
that's pretty good.
When I was in high school, I didn't do too well in science figuring
sound, light, electricity, etc., but straight math I usually get. Gavin
put a lot of effort into that analysis e-mail, but you did a great job
coming up with a tangible formula. If you had more specifics, you could
probably get an approximation. If you take the cutout of the top of the
cone, the -(Pi)(r)(s), then you would know the diameter from one side of
the cutout to the other. Then, if you knew the depth of the dome, then
can't you find the surface area? I know the circle is easier, but is
there a formula for that? I can't recall right now.
Are there any science buffs here that are good explaining sound waves?
That would be an interesting perspective.
Thanks a lot,
Kristena
For Marty (off the topic, but somewhat related)-
When I was tutoring a 7th grader recently, the child used a formula for
the surface area of a cylinder that I had never seen before. I had
always found the area of the two ends, (2)(Pi)(r^2), the surface area of
the outside, (Pi)(d)(h), then added the two results. I don't remember
the formula the student gave me, but if you happen to know it, could you
please send it to me? I should have wrote it down!
On Wed, 24 Nov 2004 12:02:43 -0800 (GMT-08:00)
writes:
>
> That's good analysis, Gavin.
> The surface area formula for a cone, ( I just looked it up) is not
> too bad. It's (Pi)(r)(s) where s is the slant height of the cone,
> i.e. it can figured without the depth of the cone. But it does get
> more complicated when ya consider that the speaker isn't a complete
> the cone. It has that dome in the middle. If that dome is of large
> sperical radius, then I figure we can approximate it as flat. So
> heres what I'm figuring as a more complete form for the surface
> area:
>
> [(Pi)(R)(S) - (Pi)(r)(s)] + (Pi) r^2
>
> where R is the radius of the speaker, r is the 2d radius of the dome
> (not the spherical radius), S is the slant height of the speaker, s
> is the slant height of the section of the cone that got removed.
>
> -Marty
