quote:

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How many forum members does it takes to change a light bulb?

1 to change the light bulb and to post that the light bulb has been changed
14 to share similar experiences of changing light bulbs and how the light
bulb could have been changed differently
7 to caution about the dangers of changing light bulbs
1 to move it to the Lighting section
2 to argue then move it to the Electricals section
7 to point out spelling/grammar errors in posts about changing light bulbs
5 to flame the spell checkers
3 to correct spelling/grammar flames
6 to argue over whether it's "lightbulb" or "light bulb" ... another 6 to
condemn those 6 as stupid
2 industry professionals to inform the group that the proper term is "lamp"
15 know-it-alls who claim they were in the industry, and that "light bulb"
is perfectly correct
19 to post that this forum is not about light bulbs and to please take this
discussion to a lightbulb forum
11 to defend the posting to this forum saying that we all use light bulbs
and therefore the posts are relevant to this forum
36 to debate which method of changing light bulbs is superior, where to buy
the best light bulbs, what brand of light bulbs work best for this technique
and what brands are faulty
7 to post URL's where one can see examples of different light bulbs
4 to post that the URL's were posted incorrectly and then post the corrected
URL's
3 to post about links they found from the URL's that are relevant to this
group which makes light bulbs relevant to this group
13 to link all posts to date, quote them in their entirety including all
headers and signatures, and add "Me too"
5 to post to the group that they will no longer post because they cannot
handle the light bulb controversy
4 to say "didn't we go through this already a short time ago?"
13 to say "do a Google search on light bulbs before posting questions about
light bulbs"
1 forum lurker to respond to the original post 6 months from now and start
it all over again.

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quote:

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Originally posted by stevebubs
OK...algebra time

time = distance / velocity

v=overall velocity
d=overall distance
v1=speed for first half (20mph)
v2=speed for second half (x mph)
d1=distance travelled for first half of journey
d2=distance travelled for second half of journey

t = d/v = (d1/v1) + (d2/v2)

t is a constant and irrelevant other than to be equal to both sides; we can safely disregard it

d1=d2=d/2, so we can substitute d1 and d2 for d/2

t=d/v=(d/(2v1))+(d/(2v2))

d is common on the right

d/v=d((1/(2v1))+(1/(2v2)))

divide both side by d

1/v=(1/(2v1))+(1/(2v2))

v=40
v1=20

=> 1/40=(1/(2x20))+(1/(2v2))

=> 1/40=(1/40)+(1/(2v2))

subtract 1/40 from each side

=> 0 = 1/(2v2)

multiple both sides by 2

=> 0 = 1/v2

Therefore impossible

PS Yes - I am bored!


[Edited on 3/8/05 by stevebubs]

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