- This topic has 2,250 replies, 179 voices, and was last updated 3 years, 1 month ago by .
-
Posts
-
intellegent-
That’s a good point – if there was no atmosphere, the brochos on lightning and thunder (no weather) shiluach hakan (no flying) would also be affected, among many others.
I was specifically asking about Shabbos and Yom Tov.
The answer is – there would be no bain hashmoshos. That means that Shabbos and Yom Tov would be shortened slightly for someone living on the equator, and by a larger amount the further one moved from the equator.
Currently, since the equator is moving fastest, its twilight period is shortest.
Atmospheric refraction is what causes the sky to remain somewhat light after the sun dips below the horizon (and lighten before sunrise), but without it daybreak and nightfall would be instant.
Beams of light traveling thru the air are only visible because of water vapor, smoke or dust in the air that they illuminate, which is what I think is what you meant (the moon, with no atmosphere, has a night and day).
I can only try,
that is v. interesting, but if it is true (and I’m not sure that it is) that light can only be seen through matter, then your argument does not make sense because there would be no light at all.
intellegent-
The info below was cut-and-pasted from a discussion about lasers.
It contains a reasonably concise explanation of what I tried to describe above.
Why does the laser not create a beam of light that you can see as it travels through the air to its destination (like a flashlight)?
You can only see light travel across a room if something in the air scatters that light toward you. If there is dust, smoke, or mist in the air, you will see that light pass through it. You will see a flashlight beam scattered by these particles and you will also see a laser beam. In that respect, the two kinds of light are very similar. Some laser beams are so intense that the Rayleigh scattering (the scattering that creates the blue sky) is strong enough to make the beams visible even in perfectly dust-free air. The beams shown in class are not that strong and would only be visible if something in the air scattered their light toward your eyes.
Losing Weight: Solution
Assuming the shoe-soles had no height:
(I wonder what they discussed on their trip)
So why does a flashlight show the beam and not the laser?
intelligent-
The specific laser being discussed is projecting its beam where there are no vapors, dusts or smoke in the air. The answer portion states If there is dust, smoke, or mist in the air, you will see that light pass through it. You will see a flashlight beam scattered by these particles and you will also see a laser beam.
The atmosphere can and does distort light to an extent, which is why computer enhancement of satellite photos taken at extreme magnification is helpful, and even necessary in some cases.
Thermal currents can also cause distortion aka heat waves.
Wake Up! Wake Up! Answer:
Which planet has two sunrises and sunsets on the same day?
Mercury.
How is that possible?
Mercury rotates in a little less than 59 Earth-days, and circles the sun about every 88 Earth-days.
That should fit the first scenario listed above, right?
Well, almost.
ICOT – very interesting! I was quite an amateur astonomer when I was young, but I didn’t know that.
When I saw your riddle, I immediately thought of Mercury and that you had made a mistake (but I was waiting for your answer to say so, and good thing I did!). You see, I read somewhere years ago that on Mercury it appears that the Sun reverses its course in the sky every day (i.e. Mercury day) around noon time because of the refraction of light in the intense heat. I thought that you were thinking of this and that you had just assumed it could also happen at sunrise.
Do you have any idea if that scientific “fact” that I mentioned is still considered a fact? Or is my brain hampered by being old enough to remember Mariner 10?
I can only try
I still don’t get why we don’t see a laser beam. What are you referring to by a laser beam? Maybe i am misunderstanding you. Isnt that the light that you don’t see the beam?
The laser is very concentrated light, so less of it strikes dust particles. Therefore, it is rare that enough light is reflected into your eyes to be able to see the beam (unless you shine it in a misty room, then you will see it). A flashlight beam is extremely unconcentrated so it is almost guaranteed that some will be sent your way.
ICOT, am I correct?
squeak-
Several misconceptions about Mercury were corrected relatively recently.
intelligent-
A laser can be a different color within the visible spectrum (i.e. red, green, blue), as well as above or below it.
squeak-
I can only try
okay, i get the basic idea. Thanks for the science discussion! (I happen to like science.)
intellegent-
It’s my pleasure – the underlying “why” behind how things work is something I find very interesting.
What’s Next?
Depicted below are five rolls of five dice, with the resulting numbers of each roll.
Can you figure out what number should follow the sixth roll (and why)?
(from an online logic puzzle)
??????? ??????? ??????? ??????? ???????
?o o? ? ? ?o o? ? o? ?o o?
? ? ? o ? ?o o? ? o ? ?o o? = 2
?o o? ? ? ?o o? ?o ? ?o o?
??????? ??????? ??????? ??????? ???????
??????? ??????? ??????? ??????? ???????
?o o? ?o o? ?o o? ?o o? ?o o?
? o ? ?o o? ? o ? ? ? ? ? = 8
?o o? ?o o? ?o o? ?o o? ?o o?
??????? ??????? ??????? ??????? ???????
??????? ??????? ??????? ??????? ???????
?o ? ?o o? ?o o? ?o o? ?o o?
? o ? ? o ? ? o ? ? o ? ?o o? = 14
? o? ?o o? ?o o? ?o o? ?o o?
??????? ??????? ??????? ??????? ???????
??????? ??????? ??????? ??????? ???????
?o o? ?o o? ? o? ? ? ?o o?
? ? ?o o? ? ? ? o ? ? ? = 0
?o o? ?o o? ?o ? ? ? ?o o?
??????? ??????? ??????? ??????? ???????
??????? ??????? ??????? ??????? ???????
?o o? ?o ? ? o? ? ? ? o?
? ? ? o ? ? ? ? o ? ? o ? = 4
?o o? ? o? ?o ? ? ? ?o ?
??????? ??????? ??????? ??????? ???????
??????? ??????? ??????? ??????? ???????
?o o? ?o o? ?o o? ?o ? ? o?
?o o? ? o ? ?o o? ? ? ? ? = ?
?o o? ?o o? ?o o? ? o? ?o ?
??????? ??????? ??????? ??????? ???????Missing:
For the kids –
Which event doesn’t occur during the year 2008?
It occurs once each year on the Hebrew calender.
I heard this same question about the year 2000 – Mod 42
Does it start with a 10?
Missing:
Mod 42-
You remembered that off the top of your head? Impressive.
squeak-
You got it!
That’s an event? I guess I know what you meant though, otherwise I could have said any number from 5-22.
We have already established that Mod42 = Deep Thought and it is therefore trivial for him to recall events from the bottom of his head as well.
What’s Next? (the dice one) Answer:
Hints for this puzzle were:
a) the puzzle name is “petals on the rose”.
b) the answer is always an even number (including possibly zero).
Since these hints didn’t help me, I omitted them.
If you want to try to solve the puzzle with these hints STOP READING NOW.
==================================================================================
==================================================================================
The answer is: All dice which have a dot in the center have all their other dots (petals) added.
A one has no other dots.
A three has two other dots.
A five has four other dots.
The two, four and six have no center dot.
asara b’teves (I checked a calander)
Doctors:
(a) The number of doctors in the US is 700,000
(b) Accidental deaths caused by physicians per year are 120,000
(c) Accidental deaths per physician is 0.17
Guns:
(a) The number of gun owners in the US is 80,000,000
(b) Accidental gun deaths per year is 1,500
(c) Accidental deaths per gun owner is 0.000019
So, statistically, doctors are approximately 9,000 times more dangerous than gun owners.
Remember: Guns don’t kill people; doctors do.
Not everyone has a gun, but almost everyone has a doctor.
Please alert your friends to this alarming threat. Doctors should be banned, or at least more strictly controlled, before this gets more out of hand.
Out of concern for general public safety, there should be no statistics published about lawyers for fear the shock would cause people to panic and seek a doctor’s assistance.
Curious, I direct you to Freakanomics. The author has an essay on exactly this topic (though he uses swimming pools rather than doctors).
Is it true that there is a leap year (Feb. 29) every 4 years (in the secular calendar)?
I think this is the first time Joseph is asking asking and doesnt know the answer to something…
lol is it a riddle or a question? cuz i’d answer “yes” but there might be a catch.
No, Joseph.
Joseph,
I think it’s generally true, except for years that are divisible by 100 (such as 2000 or 2100).
No one has answered it precisely.
anon – not the year 2000, you should remember this.
Anyway, it’s not a riddle – it’s a trivia question. Maybe we can have a trivia thread. I’ll post the full answer there.
anon – i think it depends on which calendar you’re following. there have been many over the course of history and they’re all slightly different. (i mean the solar ones. the lunar calendar is very different)
I’m not sure if this was already asked, I don’t have time to go through the entire thread and parts that I missed but here is a riddle:
On what date on the Jewish calendar do we sometimes say Hallel and sometimes say Tachanun?
OOh ooh, can I chap this one?
do you know the answer mod42
anon almost got it right. The additional proviso being that if the year is divisible by 400, it is a leap year.
I know the answer. Go ahead sqeak
That would be the 3rd day of Teves. If R”CH Teves is two days, then it is a regular day. If R”CH is one day, then it is the last day of Chanuka.
Joseph-
A solar year is approximately 365.2422 days long. The Julian Calendar rounded the value to 365.25 and had a leap year every four years (1/4 = .25). Pope Gregory the 10th, 11th, 12th, 13th or 14th(I forget what number) realized the mistake and tried to fix it.
As of Thursday, October 4th 1582 the Julian Calendar ceased to exist and the next day the Gregorian Calendar took over with the date being Friday, October 15th 1582. (The skipped days compensated for the slight decimal error over close to 16 centuries.)
The new calendar calculates the fractional part of the day as .2425 which is equal to 97/400. Therefore 97 out of 400 years are leap years.
In general a year that is divisible by 4 is a leap year. The exception to that rule is if the year is divisible by 100. The exception to that rule is if the year is divisible by 400.
1892, 1896, 1904 and 2000 were leap years.
1700, 1800 and 1900 were not. 2100 will be the next multiple of 4 that’s not a leap year.
WB Dr. Pepper! See squeak’s brand new thread.
HERE IS A RIDDLE I RECENTLY MADE.
The facts- The police interrogated 4 people. They know one of them is a murderer, one a witness, one knows who did it and one is innocent.
THERE IS ONE COMPLETE LIAR, ONE COMPLETE TRUTH-TELLER, AND TWO ARE HALF WAY.
THEY EACH SAID TWO STATEMENTS.
YOU WILL FIGURE OUT EXACTLY WHO EVERYONE IS WITH ONLY ONE POSSABLE WAY FOR EVERYONE.
THIS IS WHAT THEY SAID…
A LEE TUCKER – I DID NOT KILL HIM; I DON’T KNOW WHO DID KILL HIM
B LEROY LANDRY- I DID NOT KILL HIM; I WAS NOT AT THE MURDER
C ICH-BIN A. MATVAV- I DID NOT KILL HIM; ‘A’ WAS NOT WITH ME ATTHE MURDER.
D I.M.A. SHMOIGEL- I DID NOT KILL HIM; ‘A’ IS SAYING THE COMPLETE TRUTH.
NOTE: IF C SECOND STATEMENT IS FALSE IT WILL BE A WAS NOT WITH ME ETC. IF D STATEMENT IS FALSE IT WILL
BE THAT A IS NOT SAYING COMPLETE TRUTH. [ALTHOUGH ME AND MY CHAVRUSAH CHESBONNED A VERY LUMDISHE CALCULATION THAT IF D IS SAYING A IS SAYING A COMPLETE LIE [THIS IS ONLY IF HE IS LYING] THE REST OF THE RIDDLE WON’T WORK OUT. TRY IT WHEN YOU ARE DONE]
Two suspects are arrested by the police. The police have insufficient evidence for a conviction, and having separated both prisoners, visit each of them to offer the same deal. If one testifies for the prosecution against the other and the other remains silent, the betrayer goes free and the silent accomplice receives the full 10 year sentence. If both remain silent, both prisoners are sentenced to only six months in jail on a minor charge. If each betrays the other, each receives a five-year sentence. Each prisoner must choose to betray the other or to remain silent. Each one is assured that the other would not know about the betrayal before the end of the investigation. How should the prisoners act?
Assume that each prisoner prefers shorter sentences to longer ones, and that each gets no utility out of lowering the other prisoners sentence, and that there are no reputation effects from a prisoner’s decision.
AH! Game theory! At last, higher level riddles.
joseph, he should betray the other guy.
If he is silent he will either get 6 months (if the other guy is also silent) or 10 years (if his friend betrays him).
If he betrays his friend, his minimum goes down to no jail time (if the other guy is silent) and his maximum goes down to 5 years (if the other guy betrays).
so his choice is to have a range of 6 months to 10 years or to have a range of zero to 5 years.
But boy is that prosecutor unfair, lol.
Q how do u make an egg roll?
a: you tickle it!!!
lol
This joke was definitely written by a republican::::
chelsea clinon went to iraq and asked a soldier wat hes mst afraid of….he thought and then answered..osama…obama…and your mama
correction on my riddle
it said at the end if c second statement is false it would be
A was not with me etc.
it should say A WAS WITH ME
ALSO C NAME IS
ICH-BIN A. MATziv
charlie brown,
Correct. What you are describing is known as ‘strategic dominance’ in game theory. One startegy (in this case defecting to the prosecution) is better for one player regardless how the player’s opponent might play.
Ironically this is true even though each player’s individual reward would be greater if they both played cooperatively i.e. both remained silent and received a 6 month sentence, since with both acting in their rational best interest (startegic dominance) they both decided to defect and both ended up with a 5 year sentence.
CHACHAM…. I am not sure if this is right, but
A knows who did it, but not killer
B full truth- not there at all, so not murderer
C 1/2 truth, not killer but A was there…
D Liar, killer and A is lying (if A is lying means a half truth, since a half truth is equal to a lie…)
Am I close? this is a great riddle! 🙂
have some seichel,
you definitely have SOME seichel but you are slightly wrong
I wont give away the answer but by
‘A’ you say he just knows it and by c you say ‘a’ was there
also in your answer there are two witnesses ‘a’ and ‘c’ [because even if it is false ‘c’ will always be there] keep trying
never said I had all the seichel… just had some…. 😉
Um.. do I get partial credit for trying?
wait, there is the killer, the witness (who was there), someone who knows who did it (but not there) and someone innocent…right?
So C is the witness, while B wasnt there. A knows who did it and D is the killer.
how is that who is lying who is truth ….
i think it is impossible because i think you are saying A is half [he is not the murderer but he knows meaning first statement true, second false] ‘b’ complete truth [did not kill him and not there] and ‘d’ is the murderer [because whoever is the liar is the murderer]
But what about c? we only have a half left meaning that a is there. [second statement will be false]?
this is not the answer
- You must be logged in to reply to this topic.