Saw a suggestion to use a watch as a slide rule, but thought who wears a watch now with hands. Most are connected to a phone, internet and have more power than i have on my desktop
When i retired i gave up the watch, no need now, thankfully.
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I tossed the calendar on that same day, but SHE made me retrieve it (for birthdays and such). I cling to my analog watch with the black face; it’s my connection to the military watch of WWII, although mine has a titanium frame and band.
I’ll never give up being able to tell time by the position of the hands. Proud to be a Boomer!
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Our canteen at work had a clock with a dial and hands that ran anticlockwise.
It was the work of our tame electrician who commented
“Everything in this place is arse up, so I thought the clock should comply”
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I usually don’t use a watch, but when I do, it’s one with hands.
They just look nicer. I’ve got no interest in smart watches. One portable computer is enough.
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Time of day is, after all, a circular scale.
That is why Time never went metric … metric is for linear scales only
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While we are on logs… here is a challenge
Name some commonly used scales that are logarithmic
My contribution
pH
dB
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Sound in db is a log scale thats why volume controls on amps are log potentiometer…
So 2db is 10 times bigger than 1db
I think thats what i was taught but its a long time ago
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I thought, it was just the other way round: each step of 10db meant twice as much.
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.From Britannica
a 60-dB, or 6-bel, sound, such as normal speech,
is six powers of 10 (i.e., 106, or 1,000,000) times more
intense than a barely detectable sound, such as a faint
whisper, of 1 dB.
So 10Db or 1 bel is 10^1 ie 10 times bigger than 1Db
I never felt comfortable with log scales
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So the answer is actually in the middle:
A 10dB increase means a tenfold increase in perceived loudness.
Logarithmic scales always make a lot of sense, when exponential growth is involved, as they translate it into linear scales.
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Yes, a difference on the dB scale represents a ratio of two loudnesses.
and
I think if you added two sources of Db, you would multiply
their loudnesses?..because adding on a log scale is multiplication
Oh dear, my high school algebra is fading .
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Ok lets agree
Its a log scale, no matter what.
To be honest i cannot remember, i sat and thought about it and its now 45 years ago when i built my last audio amplifier and mixer. So beg forgiveness if wrong.
Only thing i do remember was buying a set of potentiometers to mix 2 record decks, microphone, and tape plus overall level. Before sterio as it was for disco use and over 500 watts into a selection of speakers. I forgot to ask for logarithmic pots and they supplied analog pots which did not work correctly so having finished assembled and boxed had to restart removing the analog to be replaced with logarithmic ones, hence doubling construction time.
After that moved to bought mixer amps and converted to teaching digital electronics instead much simpler.
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It’s actually the other way round:
log(ab) = log(a) + log(b)
hence, if you have, say, two annoying flies, each humming at log(a), you get their combined annoyingness:
log(2a) = log(2) + log(a)
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OK. Noises are additive on a log scale. That is why we use a log scale, I suppose.
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Originally thus was an easy subject but its gone a long way past my knowledge
So what other systems use logs ?
Easy star trek !
Captians log is how Jim started every show
Happy Star Wars Day
May the 4th be with you
Ha ha ha
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Well not really. Maths before technology goes back a lot further than slide rules, and can be very complicated.
The Romans had no decimal numbers. MMXXIV for the year 2024. If you think arithmetic with that sort of number system is easy, try doing your tax return in Roman numerals.
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I may have mentioned before that I saw a “mistake” in Roman numerals on a building downtown. It used to be the library. (I’m told. Must have been before my time.) Now it’s part of the museum.
The way I was taught Roman numerals that is not a proper representation. It should be MCMIV right?
Maybe that seemed too short for the space it was intended to occupy on the building?
Seems pretty silly to put that much effort into putting it on a building and getting it “wrong”.
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Never learned the roman number system except the easy stuff up to about 20 or so
Imagine if we still used it now the y2k problem would have been totally different
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You are right, but both are equal.
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Look like 1804 to me. Then again, been quite some time since I had to use them.
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