Brain Teasers
Which is Heavier?
Science
Science brain teasers require understanding of the physical or biological world and the laws that govern it.Science
If you fill a 5 gallon bucket with cold water and another 5 gallon bucket with hot water, which bucket will be heavier?
Answer
The bucket full of cold water.Cold water is heavier than hot water because its molecules are denser.
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Comments
Easy for me becuase the last unit I did in Science involved thermal explansion, but I doubt it will be as easy for every one else. Good teaser!
easy but good teaser
An Interesting fact. It's always good to read these science teasers.
Don't be disheartened by comments that will almost certainly follow telling you it was too easy. With this type of teaser you either know the answer or you don't. Many people will have learnt something new by reading your teaser. As an extra challenge people can ask themselves if the answer would be the same if the cooler water was cooled to a state where it was solid (i.e. 5 gallons of ice) and would the answer be the same if the liquid in question was not water. What would the differences in weight be for hot, cold and frozen liquids other than water (such as oil or ethanol)?
Don't be disheartened by comments that will almost certainly follow telling you it was too easy. With this type of teaser you either know the answer or you don't. Many people will have learnt something new by reading your teaser. As an extra challenge people can ask themselves if the answer would be the same if the cooler water was cooled to a state where it was solid (i.e. 5 gallons of ice) and would the answer be the same if the liquid in question was not water. What would the differences in weight be for hot, cold and frozen liquids other than water (such as oil or ethanol)?
Interesting. I automatically thought of steaming hot, nearly boiling water and thought of evaporation. Molecule spacing never occurred to me.
WAYYYYYY EASY! but i liked it
too easy!but nice!
That was pretty good. A little bit hard.
kind of obvious you think?
very interesting, good one!
Easy! Got it on my first guess!
I got it on my first guess. (But it was a 50-50 chance so I shouldn't be that happy.)
i thoght it was hard
that was easy! Yeah.
Good one! I didn't know...that's because I'm not a science buff (and probably most people on here aren't either), so good teaser. I learnt something new today. Thanks.
the cold watermolecules aren't denser. They are packed c;oser tp gether, and there are more of them om the bucket, that there are in the hot water bucket.
Billhardy: I do believe that denser means "packed closely together" or "closer together" .....
DUH.
DUH.
thats kinda easy (:
for me,that is a simple question
The answer is Cold \
make harder questions!
The answer is Cold \
make harder questions!
That's only true if the water is no colder than 4 deegrees C. Ice is 9% less dense than liquid water.
I agree with Andrew. You need to know the temp of the water to answer the question correctly. Ice floats in water because it is less dense then the liquid water around it.
Actually this is very much like my "cold and warm gasoline" teaser I submitted a few years back. This is probably not considered a duplicate though since you are talking about water and weight and mine is dealing with gasoline and volume.
I wasn't quite sure what it was....... then I read the answer. That was a very interesting fact!
Fun! But TOO EASY!!!
i love science
Wow, that's interesting!
you're right, "Smartest," but your answer is not. "Denser" does mean packed more closely together, but you used the word wrong. The Molecules are not denser, they are all the same H2O-the 5-gallon sample is denser. They both have the same volume, but the cold sample actually has more molecules. Also, when measuring the volume, the meniscus would be minutely different- the hotter sample's meniscus would be flatter, making you even put fewer molecules in your container.
Of course, this is all on a ridiculously small scale.
BTW, DUH.
Of course, this is all on a ridiculously small scale.
BTW, DUH.
Are we have heavy water!
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