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jfribrg
2010-Mar-24, 01:56 PM
My son told me of a memory device to remember the first 16 digits of e by simply knowing some "facts" about Andrew Jackson.

e = 2.718281828459045......

You just have to remember the 2. After that:
7 Jackson was the 7th president of the US
1828 1828 He was elected in 1828 and served 2 terms
45 90 45 Until the age of 90, he wore a pair of Colt 45 revolvers.

Nothing about this is significant, and that last part about the revolvers is pure fiction (he was 78 when he died, and Colt 45's would not be made for several more decades), but it is an interesting way to remember e.

Has anyone heard of this before? Are there others?

rommel543
2010-Mar-24, 02:26 PM
There are plenty of mnemonics.

"Every good boy deserves fudge" to remember the basic EDBDF treble clefs.

Or a word length mnemonic to remember pi. "How I like a drink, alcoholic of course,after the heavy lectures involving quantum mechanics." Take the length of each work and you will have the first 15 digits of Pi: 3.14159265358979. You can make it longer of course to remember more. In 1995 Hiroyuki Goto used word length mnemonic to recite 42,000 digits of Pi.

jfribrg
2010-Mar-24, 02:32 PM
I know there are plenty of mnemonics for pi and other things, but I had never heard of any mnemonics for e.

In my neck of the woods, the lines of the treble clef was "every good boy does fine", the notes between the lines was "face", and for the bass clef, it was "All cows eat grass always".

Larry Jacks
2010-Mar-24, 02:53 PM
The best mnemonic I can recall is for the electronics resistor color code. It isn't politically correct but it works. I still remember it over 30 years after learning it.

Bad Boys Rape Our Young Girls But Violet Gave Willingly.

Black = 0
Brown = 1
Red = 2
Orange = 3
Yellow = 4
Green = 5
Blue = 6
Violet = 7
Gray = 8
White = 9

Nick Theodorakis
2010-Mar-24, 03:00 PM
Shouldn't a mnemonic be easier to learn than the thing you are trying to learn in the first place? To me, I would use digits of e to remember that Jackson is the seventh president and was elected in 1828!

Nick

Fazor
2010-Mar-24, 03:00 PM
Yeah, my mnemonic for standard-tuning of a six-string guitar is less-than-BAUT-friendly, so I'll keep it to myself. It's interesting though.

I had forgotten the ones for the standard treble and bass cleff in music notation! It's been over a decade since I last played piano. I need to get me a decent fulls scale weighted keyboard, since I have no room for a piano in my house.

Kaptain K
2010-Mar-24, 03:03 PM
O Be A Fine Girl Kiss Me
astronomy

Eli the Ice man
electronics

Nick Theodorakis
2010-Mar-24, 03:06 PM
There is also a NSFW version of a mnemonic for the 12 cranial nerves.

For the geological periods of the Paleozoic Era, you can use "Can Oscar see down Mike's pants pockets?" If you call are using "Mississippian" and "Pennsylvanian" instead of "Carboniferous," that is.

Nick

Snake Charmer
2010-Mar-24, 03:16 PM
There are plenty of mnemonics.

"Every good boy deserves fudge" to remember the basic EDBDF treble clefs.

Apparently it doesn't work :)

jfribrg
2010-Mar-24, 03:21 PM
This one involves a small amount of work, but it's worked for me. The derivative of a rational funcion a/b = (bd(s) - sd(b))/b^2. Now, renaming the numerator as Hi, and the denominator as Ho, you get :

Ho d(Hi) - Hi d(Ho)
________________
Ho Ho

or "hodey hi minus hideyho over ho ho"

Why I remember that, I don't know, but I will always remember it. I know I could just use the product rule, but this is more fun.

grant hutchison
2010-Mar-24, 04:11 PM
Shouldn't a mnemonic be easier to learn than the thing you are trying to learn in the first place?Hear, hear. Because of their various repetitive patterns, the first 16 digits of e are notoriously easy to rote-learn.
It reminds me of my rhyme to remember the date of Easter:

There will be no trouble at all,
If we remember that Easter on the first Sunday after the first full moon after the vernal equinox doth fall.

Grant Hutchison

Torsten
2010-Mar-24, 04:32 PM
Mnemonics neatly eliminate man's only nemesis - insufficient cerebral storage.

Which, of course, is not true.

pghnative
2010-Mar-24, 05:17 PM
.. and for the bass clef, it was "All cows eat grass always".

Perhaps you meant to drop the "always"? There are only four notes "between the lines" on either clef. And if you decided to continue, the next note is "B", not "A".

grapes
2010-Mar-24, 05:46 PM
Take the length of each work and you will have the first 15 digits of Pi: 3.14159265358979. Word.

The speed of light (299,792,458 m/s): An Ingenious Astronomy Student Remembers My Easy Light Mnemonic

Gemini
2010-Mar-24, 05:52 PM
My way for remembering the digits of e was:
2.7 ;Andrew Jackson; Andrew Jackson; Isosceles right triangle.

tdvance
2010-Mar-24, 06:11 PM
Yeah, my mnemonic for standard-tuning of a six-string guitar is less-than-BAUT-friendly, so I'll keep it to myself. It's interesting though.

I had forgotten the ones for the standard treble and bass cleff in music notation! It's been over a decade since I last played piano. I need to get me a decent fulls scale weighted keyboard, since I have no room for a piano in my house.

Every Good Boy Does Fine, Good Boys Do Fine Always,

and for spaces, FACE, and All Cows Eat Grass.

And for the circle of fifths:

four constipated gophers died after eating beans.

tdvance
2010-Mar-24, 06:14 PM
hmmm....was never taught any for the Tenor Clef:

lines: fords and chevys eat gas

spaces: good boys do fine

HenrikOlsen
2010-Mar-24, 08:28 PM
O Be A Fine Girl Kiss Me
astronomy
Oh Be A Fine Girl Kiss Me Right Now. Slap!

redshifter
2010-Mar-24, 10:48 PM
Roy G. Biv

Red
Orange
Yellow
Green
Blue
Indigo
Violet

From 8th grade earth science class. Must've had a great teacher because I still remember this...

kleindoofy
2010-Mar-24, 11:50 PM
An old priest once taught me this one:

Rococo-Galefico-tete-tititi-philhebreh

(= Rohkohkoh-Gahlayfeekoh-taytay-teeteetee-fill-haybray)

Those are the Letters of Paul in the NT:

Romans
Corinthians (I)
Corinthians (II)

Galatians
Ephesians
Philippians
Colossians

Thessalonians (I)
Thessalonians (II)
Timothy (I)
Timothy (II)
Titus

Philemon
Hebrews

Spoken rhythmically (and with a German pronounciation), it's easy to learn and impossible to forget.

I just wish I had a memnotic to remind me of all the other memnotics I've learned over time.

swampyankee
2010-Mar-25, 12:32 AM
Perhaps oddly, I actually find it more difficult to remember how to decode the mnemonic than to actually memorize the thing.

Teachers would give me obvious, classic mnemonics and I would be stuck.

Besides, Jackson was a lousy president.

tdvance
2010-Mar-25, 02:19 AM
My HS teacher told me that "e" is 2.7 Andy Jackson Andy Jackson. I memorized the 459045 on my own later, it being a base-100 palindrome. I learned the How I need a drink one in HS as well, and it got me started. One summer when I was bored, I memorized up to 63 digits (64 "words" counting "point"---I spoke in a rhythm of 4s for easier memorization--and grouped the 4s into 4s and those into 4s, for a total of 64) with no mnennmnyonics, just brute force. I still have it...mostly, but sometimes get stuck and have to start over and THEN get it (can't restart in the middle for some reason).

kleindoofy
2010-Mar-25, 02:45 AM
It's not about numbers, but I remember this one I heard about 25 years ago: Luna mentitur.

It means "the Moon lies." It helps remember how to tell if the moon is waning or waxing.

When the Moon is waxing, it looks like a D, and when waning, like a C.

But, C = crescit ("to increase"), D = decrescit ("to decrease"); like the musical terms crescendo ("to play louder") and decrescendo ("to play softer").

So, when the Moon is waxing and shows us a D, it's lying, because it's not decreasing (decrescit), it's increasing (crescit), and vice versa when it's waning.

grapes
2010-Mar-25, 03:17 AM
So, it tells the truth in Australia? Interesting... :)

Celestial Mechanic
2010-Mar-25, 04:43 AM
{Snip!} For the geological periods of the Paleozoic Era, you can use "Can Oscar see down Mike's pants pockets?" If you call are using "Mississippian" and "Pennsylvanian" instead of "Carboniferous," that is.
The mnemonic that I learned for it (right here back in the days of BABB!) was "Campbell's Onion Soup Doesn't Make People Puke". :lol:

mugaliens
2010-Mar-25, 11:56 AM
Until the age of 90, he wore a pair of Colt 45 revolvers.

You see, I keep trying to mention stuff like this and it keeps getting me suspended.

grant hutchison
2010-Mar-25, 02:19 PM
Until the age of 90, he wore a pair of Colt 45 revolvers.You see, I keep trying to mention stuff like this and it keeps getting me suspended.Of course, the post from jfribrg has the advantage of being transparent fiction specifically concocted for a purpose that has nothing to do with guns or American presidents.

Grant Hutchison

rommel543
2010-Mar-25, 05:06 PM
It's not about numbers, but I remember this one I heard about 25 years ago: Luna mentitur.

It means "the Moon lies." It helps remember how to tell if the moon is waning or waxing.

When the Moon is waxing, it looks like a D, and when waning, like a C.

But, C = crescit ("to increase"), D = decrescit ("to decrease"); like the musical terms crescendo ("to play louder") and decrescendo ("to play softer").

So, when the Moon is waxing and shows us a D, it's lying, because it's not decreasing (decrescit), it's increasing (crescit), and vice versa when it's waning.

I always think of the moon in the terms of reading. We read from left to right but the moon goes from right to left.

J Riff
2010-Mar-25, 05:52 PM
Harry Lorayne, the magician, pioneered a memory system that had him on Carson, remembering things about 500 people he had just met briefly.
If you actually have to remember mucho numbers, there is no substitute for this system, which goes something like:
1=T or D 2 = N 3= M 4 =R and so on.
Then you make words, which turn into visual images, which can be remembered as a sequence, whereas numbers, after there's enough of them, can't.
I had the 'peg list' down up to the number 75. Sitting in a bingo parlor can help when practicing this. )

Grey
2010-Mar-25, 06:54 PM
This is also not about numbers, but it's my proof that a mnemonic device doesn't necessarily have to make any sense to work. Back in my high school biology class (many years ago now), we had to memorize all the bones in the human skeleton. Well, I was trying to remember which of the forearm bones was the radius, and which was the ulna. Well, I could see that the radius was on the same side of the arm as the thumb, and so I thought, "that's easy, R for thumb". It was actually some time later, after the class was over, that I was thinking back and suddenly realized that the letter "R", and the word "thumb" in fact have nothing whatsoever to do with each other, and so my mnemonic made no sense at all. Given that, I'm still not entirely sure how it came to mind at the time. Nevertheless, it helped me remember the right answer, and I've told the story to many people over the years, most of whom can now easily remember "R for thumb", and thus know which bone is the radius and which is the ulna.

grant hutchison
2010-Mar-25, 07:37 PM
This is also not about numbers, but it's my proof that a mnemonic device doesn't necessarily have to make any sense to work. I had a similar one when I was trying to sort out the functions of xylem and phloem in biology class: which system brings stuff up from the roots, and which brings it down from the leaves?
Easy, I thought: xylem goes z-z-z-ee-p [rising tone], and phloem goes f-f-f-oo-p [falling tone].
The fact that I could just as easily have reversed the tone change didn't occur to me until about a decade later, and it made no difference to the usefulness of the memory aid.

Grant Hutchison

jfribrg
2010-Mar-25, 09:05 PM
Here's another one I heard years ago. In a cave, which are stalagtites and which are stalagmites?

It's easy if you remember that stalagtites hold tight to the ceiling and stalagmites eventually might grow to reach the ceiling.

grant hutchison
2010-Mar-25, 09:22 PM
In a cave, which are stalagtites and which are stalagmites?That's actually spelled stalactites. :)
Hence, the mnemonic my father taught me: stalactites grow from the ceiling; stalagmites grow from the ground.

Grant Hutchison

kleindoofy
2010-Mar-25, 10:17 PM
So, it tells the truth in Australia? Interesting... :)
No, the Moon lies in Australia was well.

The Australians are so busy hanging upside down they just don't realize it. ;)

jfribrg
2010-Mar-26, 02:57 AM
When turning a faucet, it's "righty tightey, lefty loosie".

Nick Theodorakis
2010-Mar-26, 03:23 AM
When turning a faucet, it's "righty tightey, lefty loosie".

The hot and cold taps in my sink go in opposite directions.

Nick

grant hutchison
2010-Mar-26, 09:03 AM
When turning a faucet, it's "righty tightey, lefty loosie".In medical jargon, supination is the act of turning your body or hand to lie on its back; pronation is the opposite movement.
To recall the difference between supination and pronation of the hand, medical students are taught: supination secures the screw; pronation pours the pint.
I've never had a problem recalling the meaning of the words, but I sometimes struggle with the direction of rotation that tightens a conventional screw; so I've reversed the use of the mnemonic. If I can't seem to budge an overly tight screw thread I have to go through this elaborate process:
1) Supination secures the screw.
2) But I'm left-handed, so pronation secures the screw.
3) But I'm trying to undo the screw, so I should need supination.
4) Is there any reason this screw will have reversed threading?

Then I can apply a bit more force with some confidence that I'm not actually tightening the damn' thing.

Grant Hutchison

DonM435
2010-Mar-26, 01:31 PM
George Washington's birth year (1732) suggests the square root of three (1.732 ...).

In zoology, we had "Kings print checks on fancy gold slips" to remember the taxonomic hierarchy of Kingdom, Phylum, Class, Order, Family, Genus and Species.

tdvance
2010-Mar-26, 06:57 PM
When in Germany, a woman goes to "Her" bathroom, marked Herren, and a man goes to Da Men's bathroom.

Now, if you remember that's a very misleading statement, you'll get it right.

grapes
2010-Mar-27, 05:59 PM
George Washington's birth year (1732) suggests the square root of three (1.732 ...).Which one do you have to remember? :)

Or is it just that you only have to expend half the effort in memorizing both?

To remember the geological eras, I tried to use more than the first letter: Cameron Ordered Silicon Devices, but Missed the Pencil Permits, (Paleozoic eras) Triangle Juries Created (Mesozoic) Terrible Quarrels (OK, so it doesn't work anymore).

grant hutchison
2010-Mar-27, 07:24 PM
To remember the geological eras ...The one that has stuck usefully in my mind is: "Pregnant camels often sit down carefully. Perhaps their joints creak. Early oiling might prevent permanent rheumatism."

Grant Hutchison

DonM435
2010-Mar-28, 03:10 AM
Which one do you have to remember? :)

Or is it just that you only have to expend half the effort in memorizing both?

To remember the geological eras, I tried to use more than the first letter: Cameron Ordered Silicon Devices, but Missed the Pencil Permits, (Paleozoic eras) Triangle Juries Created (Mesozoic) Terrible Quarrels (OK, so it doesn't work anymore).

Mt high school history teacher told me the 1732 and 1.732 trick. For some reason, I remembered both. And it helped.

On a later American History test, I had to date an event. Somehow I was able to use Washington's birth year to anchor a calculation that got me there.

On an Algebra final, we had to derive the square root of three. I had to show the weork, but it was good to know in advance what to expect as the answer.

eugenek
2010-Mar-28, 03:33 PM
While Running Backwards You Vomit (White, Red, Black, Yellow, Violet).

and

Boy On Girl Brings Satisfaction (Blue, Orange, Green, Brown, Slate).

The first and second sequence, respectively, for 25-pair twisted cables used in telephony. It still required some additional memorization since the 'B' could be three different colors. But, they are in correct alphabetical order with one another.

tdvance
2010-Mar-28, 06:04 PM
An engineer who taught my Phys101 class told us: black is the color of death and that's what will surround you if you touch the black wire (in AC wiring). I never forgot "black is hot" after that. With car batteries, it was easy to transfer to that as "black is negative", since death is kind of negative. He told us that white is neutral. Now, in my house, I take apart a junction box and find black twisted onto white.... ok, this white wire ain't neutral no more!

mugaliens
2010-Mar-28, 06:20 PM
I always think of the moon in the terms of reading. We read from left to right but the moon goes from right to left.

It does in the Northern hemisphere...

grant hutchison
2010-Mar-28, 06:30 PM
An engineer who taught my Phys101 class told us: black is the color of death and that's what will surround you if you touch the black wire (in AC wiring). I never forgot "black is hot" after that.Remind me not to do any wiring work in the USA. :) The older wiring in my house has a black neutral and a red live, which is the older UK standard.

Grant Hutchison

Grey
2010-Mar-29, 03:51 PM
Remind me not to do any wiring work in the USA. :) The older wiring in my house has a black neutral and a red live, which is the older UK standard.My recommendation is to always assume that, for any wiring you did not do yourself, you should not trust that any standard color scheme applies. Test the wires with a meter to find out what things are hot.

grant hutchison
2010-Mar-29, 04:11 PM
My recommendation is to always assume that, for any wiring you did not do yourself, you should not trust that any standard color scheme applies. Test the wires with a meter to find out what things are hot.Indeed. When we moved into our last house we got the gas boiler serviced, and they discovered an earth leakage current in the gas pipes. The gas fitter turned off our gas supply until a qualified electrician fixed and signed off on the electrical problem. The qualified electrician fixed the insulation fault that was generating the earth leakage, but left me with a power socket in which the live and neutral were reversed.

Grant Hutchison

Eta C
2010-Mar-29, 04:25 PM
This one stuck with me from high school on the relations between the trig functions (sin,cos,tan) and the sides of a right triangle. Oscar Had A Heap Of Apples.

Sin = opposite over hypotenuse

grant hutchison
2010-Mar-29, 04:41 PM
This one stuck with me from high school on the relations between the trig functions (sin,cos,tan) and the sides of a right triangle. Oscar Had A Heap Of Apples.

Sin = opposite over hypotenuse
Tan = opposite over adjacentWe were taught to remember the word "SOHCAHTOA", which serves the same functions, if you'll pardon the pun. :)

Grant Hutchison

jfribrg
2010-Mar-29, 04:51 PM
I remember SOHCAHTOA well. I still use it.

Then of course there is the mneumonic to remember whether it's a harmless King Snake or a poisonous Coral Snake: Red against yellow will kill a fellow. Red againsh black is a friend of Jack

grant hutchison
2010-Mar-29, 05:07 PM
Then of course there is the mneumonic to remember whether it's a harmless King Snake or a poisonous Coral Snake: Red against yellow will kill a fellow. Red againsh black is a friend of JackIt's probably worth knowing that one only applies in North America.

Grant Hutchison

Grey
2010-Mar-29, 05:16 PM
As with wiring, I'll recommend global caution with snakes. Don't go looking closely to see whether the red stripes are touching the yellow stripes or not. Just give the snake the benefit of the doubt, and back slowly away. :)