NationStates Jolt Archive

I have been wondering lately, does that experiment work where you take two cups and punch a hole in the bottom of them and tie a string between both cups then talk into them? If anyone has had success with this please tell me. It just doesn't seem all that plausable to me and as a younger kid I was never able to get this to work.

I did it with metal cans and some thin copper wire. Pulled very tight, the system works over a short distance.

String doesn't get taut enough.

I have been wondering lately, does that experiment work where you take two cups and punch a hole in the bottom of them and tie a string between both cups then talk into them? If anyone has had success with this please tell me. It just doesn't seem all that plausable to me and as a younger kid I was never able to get this to work.
It should be two tin cans, and the string has to be taunt between them in order for it to work.

Technically it does. Sound travels better through a solid object than it does air, and moves slightly faster, and so it should work.
the thing is, given that you're likely to be able to hear the person ANYWAY, it really doesn't work all that well.

I have been wondering lately, does that experiment work where you take two cups and punch a hole in the bottom of them and tie a string between both cups then talk into them? If anyone has had success with this please tell me. It just doesn't seem all that plausable to me and as a younger kid I was never able to get this to work.

Yeah it works. Ya gotta make sure that the string is sealed against the sides of the hole, so the vibrations run along the line, I believe it may also help if the line is taught.

Why? Do you have a cool new tree fort? :)

Yeah it works. Ya gotta make sure that the string is sealed against the sides of the hole, so the vibrations run along the line, I believe it may also help if the line is taught.

Why? Do you have a cool new tree fort? :)

haha, no nothing like that :p I was just reminiscing about my kindergarden days and how frustrated I was when I couldn't get it to work. This has inspired me to try it again though.

You know the Seattle Science center had a HUGE version of one of those somewhere...I think it was by one of the entrances. Anyway, pity about that lack of tree fort. I think all of us still want one...or is it just me? ;)

you wanna do a cool experiment with sound waves, go to Chichen Itza in the Yucatan Peninsula of Mexico...

go to the 100ish-yard-long football-type field with a friend, and stand on opposite ends, about 100 yards apart...

then carry on a normal conversation... you can whisper and hear each other. it's really quite exhilerating.

you wanna do a cool experiment with sound waves, go to Chichen Itza in the Yucatan Peninsula of Mexico...

go to the 100ish-yard-long football-type field with a friend, and stand on opposite ends, about 100 yards apart...

then carry on a normal conversation... you can whisper and hear each other. it's really quite exhilerating.

And what makes this phenomenon possible?

I had a wonderful free-standing one that my grandfather built. As my family moved from place to place, the treehouse came with us. It currently sits at my last house, half the country away. I'll never forget that treehouse.

And what makes this phenomenon possible?

I do not know... some trick with acoustics I suppose.

I do not know... some trick with acoustics I suppose.

Is there any amplification involved due to any nearby land formations? For instance if someone were to yell at you on the opposite end would it be loud enough to cause pain to your ears?

It's to do with the wavelengths of sound, and their being focused, in phase, to the location. It's like light, if you turn on a lightbulb, you get hit with a bit of the light. if you focus it in one direction, it's much brighter to the person receiving it. Same with sound. Also, if you have it so the soundwaves arrive at exactly the same time, in phase, then you won't have any cancelling each other out. For example, if you had, to use the light example again, two light bulbs set to deliver light at half a wavelengths distance, then you would see neither, regardless of intensity, because they cancel each other out. However sound/light in phase is much LOUDER.

It's a cumulative effect.

At the Jodrell Bank radio telescope here in the UK, there are two satellite dishes on a lawn, around 50 metres apart, mounted sideways so they are pointing at each other. Stand next to one, get a friend to stand in front of the other, and you can talk to each other. It sounds a bit tinny, but it works. Standing waves, I believe. Been a while since I've had to do acoustics though, so could be wrong.