What else did your teachers tell you. 4

[JCreamerII]

Taking a thought from the a post I just read, what did a teacher tell you as fact, that was wrong?

I had a Biology teacher tell my class that lobsters were red. We started a new club, LAG "Lobsters are Green". He obviously never saw one in a tank. Again this goes back over 40 years. But he was totally convinced that they were red.

Jim C.

 

[BadBigBen]

Nothing can go faster than the speed of light

well, it seems that they where right after all...

Single photons obey the speed limits

http://physics.aps.org/synopsis-for/10.1103/PhysRevLett.106.243602

and I guess strongm has already touched on that information in one of his last posts... ;-)

Ben
"If it works don't fix it! If it doesn't use a sledgehammer..."
How to ask a question, when posting them to a professional forum.
Only ask questions with yes/no answers if you want "yes" or "no"

 

[mscallisto]

But what about the behavior of single photons, the fundamental quanta of light?

Should that be quantum (singular) not quanta (plural)?
I always confuse the two.

sam

 

[Annihilannic]

Plural is correct. Such as the behaviour of bricks, the fundamental components of a building.

Annihilannic.

 

[mscallisto]

Yes I have to agree.

 

[kwbMitel]

The best example I have of a teacher telling me something wrong was in statistics class.

The problem was very simple.

If you roll 3 dice, what are the odds of the same number showing on all 3 dice.

The "Correct" answer was 1 in 216. I was eventually thown out of the class for disagreeing too loudly.

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[DansDadUK]

>> If you roll 3 dice, what are the odds of the same number showing
>> on all 3 dice.

It depends on what is assumed about the meaning of "the same number"; I think that:

- Odds of the same SPECIFIC number (e.g. 6) showing on all 3 dice: 1 in 216.

- Odds of ANY number (1, or 2, or 3 , or 4, or 5, or 6) showing on all 3 dice: 1 in 36.

 

[1DMF]

If a number appears on one dice, that then enforces that a 'SPECIFIC' number must appear on the others.

As the number that appears on the first dice is irrelivant, and only matters that the other two match.

That makes the probablility of throwing the same number with the remaining two dice as 1 in 36.

However, If all three dice are thrown at the same time, to my mind surely that decreased the likely hood that they will match and so the odds would go up?

But how do you quantify that number? does the likely hood increase if the dice are thrown one at a time vs all at the same time?







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[N1GHTEYES]

does the likely hood increase if the dice are thrown one at a time vs all at the same time?

No.

Assuming the dice are fair, and that the requirement is:

If you roll 3 dice, what are the odds of the same number showing on all 3 dice.

...then the odds are 1 in 36.

The order is irrelevant and resistance is futile.

Tony

 

[1DMF]

So the fact the dice are more likely to collide with each other than they might being thrown one at a time doesn't effect the odds?

I'm not sure chaos theory agrees, but I'm sure Mike will have the answer ;-)

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[IPGuru]

The odds will always remain the same

Each die can land come to rest in any one of 6 positions.

one of these dice (weather it comes to rest first or is chosen by the thrower) then sets the parameters for the remaining 2 giving in 36 result

weather the dice have collided or not the final positions are still random so the statistical odds remain the same.


I do not Have A.D.D. im just easily, Hey look a Squirrel!

 

[1DMF]

I always thought the more external forces that are excerted on something the more random it becomes, based on chaos theory.

But I can see what you're saying as there will only ever be 6 possible resting places. Have another star!



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[IPGuru]

this question got me thinking a little so I knocked together q quick & dirty python program to test things

import random
DICE=(1,2,3,4,5,6)
SAMPLE=36000 #number of throws per sample
REPEAT=20
test=0
while test <=REPEAT:
    test+=1
    match=0
    throws=0
    while throws < SAMPLE:
        throws+=1
        d1=random.choice(DICE)
        d2=random.choice(DICE)
        d3=random.choice(DICE)
        if d1==d2 and d2==d3: match+=1
#        print d1,d2,d3,throws,match
    print throws,match,throws/match

SAMPLE is the number of throws to make in each test
REPEAT is the number of times to repeat each test
My variables will be treated as integers by python which means any floating point remainders will be stripped:- 1/2=1

running with a sample size of 36000 I get results ranging from 34-38 which I think easily falls within the margin for error for this experiment, larger sample sizes converge even closer to the predicted 36


I do not Have A.D.D. im just easily, Hey look a Squirrel!

 

[CajunCenturion]

==> Such as the behaviour of bricks, the fundamental components of a building.
It all depends on whether you consider 'bricks' a mass noun, and whether or not bricks are the only fundamental components.

Bricks are a fundamental component of a building.
Bricks are the fundamental component of a building.
Bricks are the fundamental components of a building.

All three are grammatically correct, yet each say something slightly different. I tend to think that the first is most common. Bricks, as a mass noun, are one of several fundamental components of a building.

By the same token, I think the singular version is correct with light.
Photos are the fundamental quantum of light.

With respect to statistics, the correct answer is 1 in 36. Regardless of any forces that are in play, the odds of any two dice rolling to the same number is 1 in 6. There are 36 possible outcomes and 6 of them have both dice with the same number, so the odds of matching are 6/36 = 1/6. When you add a third die, there is a 1 in 6 chance that it will match either of the other two, coupled with a 1/6 chance that the first two match third results in a 1/6 * 1/6 = 1/36 chance of all three matching.

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[strongm]

>So the fact the dice are more likely to collide with each other than they might being thrown one at a time doesn't effect the odds?


No

 

[1DMF]

IPGuru - does a computer simulation actually represent real world dice throwing?

Imperfections on the dice or the beize (cloth) they are thrown on, the way they are tossed, etc.

I wonder what result you would get doing your experiment in the real world.

Is there a reason you chose 36,000 samples?

How many times does it hapen if you just do 36?

"In complete darkness we are all the same, only our knowledge and wisdom separates us, don't let your eyes deceive you."

"If a shortcut was meant to be easy, it wouldn't be a shortcut, it would be the way!"

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[strongm]

>IPGuru - does a computer simulation actually represent real world dice throwing?

Depends ...

>How many times does it hapen if you just do 36?

What do you think?

 

[N1GHTEYES]

>How many times does it hapen if you just do 36? What do you think?

Interestingly, the answer is that you'd have nearly a 64% chance of getting 3 identical numbers.

Tony

 

[mscallisto]

[red]Photos[/red] are the fundamental quantum of light

But [red]Photos[/red] of what? LOL

 

[N1GHTEYES]

To clarify my previous statement:

If you throw 3 dice, 36 times (asuming the dice are fair), you would have a nearly 64% probability of seeing at least one case where the displayed number on all three dice was the same.

Probability is weird isn't it?

Tony

 

[mscallisto]

I have to say I did vote for "singular" first until Annihilannic's response changed my mind and now I'm still not convinced which form is correct.

Is a single photon, the fundamental quanta of light?

I may flip-flop back to singular (or not); I need Stephen Hawking's E-Address!!!.

Sam