Brain Teasers
Ketchup Sachet
Science
Science brain teasers require understanding of the physical or biological world and the laws that govern it.Science
A man picked up a plastic water bottle and filled it to the rim with water. He put a ketchup sachet in it and closed it up.
The man approached a woman and said, "If you can solve how this works, I'll give you a dollar."
The man said "down" and the sachet of ketchup suddenly went down. Then he said "up" and it went up. Then he said "down", and when it was halfway down, he said "stay" and it stayed.
How did he do this?
The man approached a woman and said, "If you can solve how this works, I'll give you a dollar."
The man said "down" and the sachet of ketchup suddenly went down. Then he said "up" and it went up. Then he said "down", and when it was halfway down, he said "stay" and it stayed.
How did he do this?
Hint
Think pressure.Answer
He did it by adding pressure to the bottom. When there is less pressure, it rises. When there is more pressure, it lowers. If you add just the right pressure, it will stay.You can perform this with lots of practice in front of a mirror. It will shock your friends, most likely.
You can find a ketchup sachet at your local fast food restaurant (ex: Burger King, McDonald's, etc.)
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Comments
Fun!
ive done the same thing just using a straw and paper clip. Good teaser though
Is a sachet like a packet?
that was very clever
Very clever and cool trick. I didn't think hard enough to get it the first time I read it.
reeal ez
i guessed and got right
i guessed and got right
a sachet is like the things you rip and squeeze the ketchup lol
Very interesting, I will post again after I try this with my children, ages 5 & 12. Should be very fun for them, lol! Thanks!
you didn't even say how you add pressure
Mar 18, 2009
You add pressure by squeezing the plastic bottle.
(Remember it is closed up tight so you can use pressure on it)
(Remember it is closed up tight so you can use pressure on it)
I thought squeezing too
How about saying "up", then lifting the bottle, saying "down" and lowering it...the ketchup would go up and down
So...did she get the $1?
amazing!!!!!!!!!
I was thinking that he moved the ketchup by tilting the bottle. Though in hindsight that wouldn't explain how he tried to astound the woman he bet a dollar with.
That was very easy! The cheap skate only offered a dollar?
Love Babe's answer.
A dollar? Would have to do better than that. My time is valuable after all.
The explanation is no explanation. This is a variation on the Cartesian Diver. The air in the packet (sachet) is compressed upon squeezing, and the bouyancy of the packet is lessened so it sinks. Practice allows you to squeeze the bottle with enough force to allow the packet to float in the middle. It's all about Boyle's law of pressure and volume.
buoyancy
Still wanna know if she got the money...
and I want to also know if "she" got the money ....
It's a sexist riddle. Why was "he" a "he" and "she" a "she" ???
Why not "one person" asking "another person".
And I not just being "politically correct" or "picky" here.
The Braingle Judges are - currently - so "gun-shy" about certain attributes of some categories (riddles, language, rebuses) that they feel would cause user criticism of the judges decisions that they are rejecting absolutely solid submittals.
So ... why choosing such a "sexist" one for TOTD !!!!
Hmmmmmm ????
Jaye
It's a sexist riddle. Why was "he" a "he" and "she" a "she" ???
Why not "one person" asking "another person".
And I not just being "politically correct" or "picky" here.
The Braingle Judges are - currently - so "gun-shy" about certain attributes of some categories (riddles, language, rebuses) that they feel would cause user criticism of the judges decisions that they are rejecting absolutely solid submittals.
So ... why choosing such a "sexist" one for TOTD !!!!
Hmmmmmm ????
Jaye
( someone isgetting picky (
Did she get the buck or no?!
I found this very interesting. Clearly, the ketchup sacket was controlled by squeezing and releasing the bottle,but my intuition was that squeezing the bottle would cause the packet to rise. If figured if the water was pressurized, then things float better in dense water than in less dense water. However, I did not see that the volume of the ketchup pachet would decrease to counter that. So, although I knew squeezing was the solution, I did not understand the science. Thanks for teaching me something new!
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