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]

# home stereo impedance matching

I have a pair of old (relatively) Bose 501 speakers that are marked as 4
Ohms, that I would like to use with a new receiver that only offers 8-16
ohm connections. From what I've been able to establish, higher end
speakers tend to be of the 4 Ohm variety due to greater power associated
with lower resistance.
What types of problems can I expect if I use 4 Ohm speakers with my 8
Ohm system?
If my only problem will be reduced performance, then I'm not terribly
concerned. If I will cause permanent damage to my new receiver I think
I'll leave the speakers in storage.
In the past, my father had wired a 4 Ohm resistor (rated at 15 Watts) in
series with the speaker so that the amp would see 8 Ohms. Is it that
easy?
Cheers,
Matt

"An expert is a man who has made all the mistakes which can be made in a
very narrow field."

- Niels Bohr

-----Original Message-----
From: Forum for Physics Educators [mailto:PHYS-L@lists.nau.edu] On
Behalf Of Justin Parke
Sent: Tuesday, February 17, 2004 1:54 PM
To: PHYS-L@lists.nau.edu
Subject: Re: rolling

I just discovered that the latest edition of Halliday, Resnick, and
Walker has the correct answers (i.e. .5 L and L) in the back of the
book!

Justin

In a message dated 2/4/2004 8:11:12 AM Eastern Standard Time,
FIZIX29@AOL.COM writes:

I need some help with the following question from Halliday et al
(6th=
ed.),
ch. 12 question 5:

"A woman rolls a cylindrical drum, by means of a board on top,
throug=
h the
distance L/2, which is half the board's length. The drum rolls
smoot=
hly, and
the board does not slide over the drum.
a) What length of board has rolled over the top of the drum?
b) How far has the woman walked?"

The answers in the book are L and 1.5 L. I am not sure I understand
=
what is
meant by "what length of board has rolled over the top of the drum."
=
It seems
to me that it should be L/2. If the questions means how
far has the =
board
moved with respect to the ground then I agree it is L.

Answers in algebraic form (plus verbal explanations) are
preferable t=
o
strictly verbal arguments.

Justin

Justin Parke
Oakland Mills High School
Columbia, MD