Brain Teasers
Water or Ice?
Which weighs more: a gallon of liquid water or a gallon of ice?
(With "weight" meaning, weight on the same planet, at the same location -- so literally, "which has more mass?")
(With "weight" meaning, weight on the same planet, at the same location -- so literally, "which has more mass?")
Answer
A gallon of liquid water weighs more than a gallon of ice.Many people might be thinking of an actual gallon jug of water, weighed at liquid, and weighed frozen (in which case they would be equal, if you remove any condensation or frost). But the question does not refer to a jug; it refers to a gallon. A gallon is a precise measurement of liquid capacity. Ice is less dense than liquid water, so a precise gallon of ice weighs slightly less than a precise gallon of water.
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Good one :poop:
Thanks... I think?
Good one again
Good science question, although not hard. By the way a gallon of water weighs about 8 pounds. Not sure how much a gallon of ice weights but as you noted it is less than that.
I think a gallon of water weighs precisely 8 pounds, right? Because the English weight system is based upon the density of water. And a gallon of ice would only weigh slightly, slightly less.
Mainly the trick is supposed to be that people might imagine having a gallon of water, freezing it, and assume that it is still a "gallon."
Mainly the trick is supposed to be that people might imagine having a gallon of water, freezing it, and assume that it is still a "gallon."
OK ..... science wizards !!!!
What about this one?
"Which weighs more .... a pound of feathers or a pound of lead?"
I know it's an OLDIE pre-gradeschool joke but I also read recently on the internet (so it's GOT to be true ... right? )
that almost half of US college grads who were asked that question either got it wrong or .....
... appeared to have to "think about it"!
Is there some trick to that one?
What about this one?
"Which weighs more .... a pound of feathers or a pound of lead?"
I know it's an OLDIE pre-gradeschool joke but I also read recently on the internet (so it's GOT to be true ... right? )
that almost half of US college grads who were asked that question either got it wrong or .....
... appeared to have to "think about it"!
Is there some trick to that one?
The trick basically stems from the whole weight/mass confusion. But most scientifically inclined people should get it. Most college grads are drunken idiots anyway. Doesn't take much to merely pass.
Good teaser. I thought it was a trick question, but was thinking of another oldie which was in pounds and not gallons so I should have been more aware. Oh well!
All you had to do was remember that ice floats in water, and hence must be less dense tha water, there therefore lighter than an equal volume of water. Of course, when one considers that a gallon is a liquid measure, and ice is a solid, one might wonder what it means to talk about "a gallon of ice."
Nothing like a little science to get the brain in motion for the day; thanks!
Great point, lukasiwicz, I didn't even think about that! It is probably inaccurate to say a "gallon of ice."
I think that because water expands when frozen, ice would take up more space. Therefore a gallon of water when frozen would be more than a gallon. Ergo, a gallon of water would weigh more than a gallon of ice.
Simple to figure with no scientific knowledge.
Simple to figure with no scientific knowledge.
Sorry I forgot to mention this was a great teaser. Thanks.
Hey ... eighsse ....
DOUBLE congrats are in order.
Great teaser AND TOTD !!!!
How nice !!
BB02
DOUBLE congrats are in order.
Great teaser AND TOTD !!!!
How nice !!
BB02
Hey thanks everybody
I got the right answer because it just made good sense to me. Anyway, it was a good teaser and thanks for posting. Not enough people around any more. SAD!!
Cry some 'croc tears' Babe.
You, Habsie, and others raised such a stink last year when I and brother Jay (BadBunnee02) pointed this out ... and why .... that so few people were now visiting Braingle and that Braingle 'was dying' ....
That you got Jay (BadBunnee02) ALMOST kicked off Braingle. He was KARMAed !!!! and is still restricted (can't post, etc.)
We've contacted the Eds ... & Jake but have received (mostly) little but BS answers.
We shall, certainly, keep trying...
AND (of course) .. still LAUGHING !!!!!!!!!!!!!!
Oh ... by the way ... eighssee (sp) ... STILL A GREAT TEASER !!!!!!!!!!!!!
Keep it up !!!!!!!!!!!!!!!!
Jaye (and ... for BB02 - who can't post STILL !!!!!!!!!!!!!!!!!!)
You, Habsie, and others raised such a stink last year when I and brother Jay (BadBunnee02) pointed this out ... and why .... that so few people were now visiting Braingle and that Braingle 'was dying' ....
That you got Jay (BadBunnee02) ALMOST kicked off Braingle. He was KARMAed !!!! and is still restricted (can't post, etc.)
We've contacted the Eds ... & Jake but have received (mostly) little but BS answers.
We shall, certainly, keep trying...
AND (of course) .. still LAUGHING !!!!!!!!!!!!!!
Oh ... by the way ... eighssee (sp) ... STILL A GREAT TEASER !!!!!!!!!!!!!
Keep it up !!!!!!!!!!!!!!!!
Jaye (and ... for BB02 - who can't post STILL !!!!!!!!!!!!!!!!!!)
I enjoyed this. I felt it was easy, but it still gave me pause before deciding on my 'final answer.
Gallon is defined as a measure of volume. When specifying liquid volumes for trade, a temperature is also provided, fixing the amount of liquid filling that volume For example, a gallon of gasoline is determined at 60 degrees F.
In the U.S., there is the concept of a "dry gallon" based on the bushel, but it is not officially used in trade law. I have no idea if this would apply to ice. However, a dry gallon is smaller than a liquid gallon, so a dry gallon of ice would weigh even less.
The density of water varies from 0.9998 g/cubic cm near freezing to 0.95 g/cubic cm when boinling (1 ATM pressure).
The density of ice is around 0.916 g / cubic cm.
Ice is lighter than water at any temperature.
In the U.S., there is the concept of a "dry gallon" based on the bushel, but it is not officially used in trade law. I have no idea if this would apply to ice. However, a dry gallon is smaller than a liquid gallon, so a dry gallon of ice would weigh even less.
The density of water varies from 0.9998 g/cubic cm near freezing to 0.95 g/cubic cm when boinling (1 ATM pressure).
The density of ice is around 0.916 g / cubic cm.
Ice is lighter than water at any temperature.
Woohoo!!! I finally got one!
I GOT IT RIGHT!
Snow dog is correct in that there is a difference between a liquid gallon and a dry gallon. However a US dry gallon is larger than a US liquid gallon (~ 268 cu in vs. 231 cu in - https://en.wikipedia.org/wiki/Dry_gallon) allowing approx 10% for expansion of freezing (I think 9% is closer from max density @4C) - this would mean that the liquid gallon @ 231 cu in would expand to 254 cu when frozen - less than 1 dry gallon, so a dry gallon should weigh more.
After some back and forth ideas on this, I figured that if Ice floats on water, it must be lighter.
Yikes! stan_acm is correct. The dry gallon is bigger than the liquid gallon.
I still don't know if it would apply to ice.
Bottom line, I agree with Coolnana. Ice floats.
Thanks for checking stan_acm. I found the discussion on this teaser much more interesting than the teaser itself. Live on, community!
I still don't know if it would apply to ice.
Bottom line, I agree with Coolnana. Ice floats.
Thanks for checking stan_acm. I found the discussion on this teaser much more interesting than the teaser itself. Live on, community!
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A little too easy, as evidenced by the difficulty score. Pretty much everyone knows ice weighs less than water.
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