General Questions

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Famine
Aaaaah, you guys want to hear about the Coroner's Corridors... :D They used to be quite common, but there's only 6 or 7 left in the UK now (for some reason)...

Essentially it's a wide road with one lane of traffic in each direction. But in the middle there's a third lane, which may be used by overtaking vehicles in either direction. Imagine the fun you could have with that... :D
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Well, I'm familiar with those - called the more-blunt "suicide lanes" in the US. What I'm talking about is NOT a dedicated lane; it's just going 3-wide on a 2-wide road, with 1 of the 3 going in the opposite direction.
:nervous:

wfooshee
Yeah, we do that all over America in our cities, where there's a center lane, not for passing but for left turns, from either side. People use it as a merge lane, a passing lane, to cheat to get to the next light if they're actually turning left there, etc.
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Actually, in Philadelphia, that's used to increase the parking capacity of any given street by 25-50%.
 
Famine
Aaaaah, you guys want to hear about the Coroner's Corridors... :D They used to be quite common, but there's only 6 or 7 left in the UK now (for some reason)...

Essentially it's a wide road with one lane of traffic in each direction. But in the middle there's a third lane, which may be used by overtaking vehicles in either direction. Imagine the fun you could have with that... :D
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As Duke has said, we have those, but they aren't for passing. They're so people can turn across track, without blocking the traffic behind them. Some people still use them as passing lanes.

EDIT: Didn't read Wfooshee's post.
 
Der Alta
Driving in Boston, the "Flash the Headlights" system is more on the lines of "You're going too slow, get out of my way."
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Yeah. If someone flashed their lights at me while overtaking, I would assume they’re pissed off.

My rule of thumb is:
  • Flashing lights at cars, or a quick-succession multi-flash at tractor trailers, means: Get out of my way!
  • A slow-succession flash at a tractor trailer means: Go ahead and pull out in front of me.
 
Sage
Similarly, if you stop, it’ll lean back, and if you accelerate, it’ll lean forwards.
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Are you using some sort of air pressure change to make that happen? Because in a car with a vacuum in the cabin, and assuming that the balloon has no leaks and no propulsion system, if you punch the gas, I'd expect it not to accelerate until it hit the rear window (neglecting gravity, because otherwise it'd be on the floor).
 
I was thinking he was joking, how it would always go the opposite direction since it floats. Maybe he really thought it would. Lighter than air doesn't mean "negative inertia."
 
Danoff
Are you using some sort of air pressure change to make that happen?
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Yes – I’m assuming a cabin with air (most of us can’t drive without oxygen ;)). There’s a very good reason he phrased the question with a helium balloon instead of just a balloon.

wfooshee
I was thinking he was joking, how it would always go the opposite direction since it floats. Maybe he really thought it would. Lighter than air doesn't mean "negative inertia."
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If you accelerate, you create a gradient of lower air pressure in the front of your car and higher air pressure in the back. The greater air pressure towards the back will displace the balloon, causing it to lean forwards.
 
Sage
If you accelerate, you create a gradient of lower air pressure in the front of your car and higher air pressure in the back. The greater air pressure towards the back will displace the balloon, causing it to lean forwards.
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I thought that's what you might be getting at, but you don't create the pressure until you actually move, so the balloon translates backward first, before air starts sloshing around.
 
A small question:

Is there an effective method for stopping the water flow to a bathroom sink not equipped with stoppage valves? (There are only attachments in place of them). The bathroom at my house is being redone, and it's been going fairly well until this problem arose...
 
Is there a shut-off further upstream? If not and it's not going to take long, turn off the water main. Just make sure that if you do that, you turn off the water heater first, as a lack of incoming water will burn it out.

And don't use the toilet. ;)
 
Sage
Yes – I’m assuming a cabin with air (most of us can’t drive without oxygen ;)). There’s a very good reason he phrased the question with a helium balloon instead of just a balloon.


If you accelerate, you create a gradient of lower air pressure in the front of your car and higher air pressure in the back. The greater air pressure towards the back will displace the balloon, causing it to lean forwards.
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It isn't a pressure differential that makes a helium balloon float, it's a weight difference. If the helium floated because it had less pressure, then the balloon wouldn't be - well, a balloon. It actually has higher pressure than the atmosphere, or it wouldn't be inflated.

If the pressure changed as much as you suggest as the car moves, your ears would experience a significant discomfort all the time.

The helium balloon will behave as any other mass, leaning backward on acceleration and forward on braking, and leaning outward in the turns. It might swing the other way after the acceleration, but that's because it's just a pendulum. Upside-down, but a pendulum. The initial motion of the balloon is governed by plain ol' inertia.

If I'm wrong, I'm wrong. Wouldn't be the first time this week. Although it would be the first time today.:dopey:
 
But what if the car with the balloon in it was on a treadmill?

:dopey:
 
wfooshee
It isn't a pressure differential that makes a helium balloon float, it's a weight difference. If the helium floated because it had less pressure, then the balloon wouldn't be - well, a balloon. It actually has higher pressure than the atmosphere, or it wouldn't be inflated.
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Nope, what makes it float is the density, which is lower than that of the air. Even the pressurized helium that allows the balloon to be inflated is light enough so that the balloon's average density is lower than that of air - same reason a metal ship floats.
 
Metar
Nope, what makes it float is the density, which is lower than that of the air. Even the pressurized helium that allows the balloon to be inflated is light enough so that the balloon's average density is lower than that of air - same reason a metal ship floats.
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I repeat:


Metar
Even the pressurized helium that allows the balloon to be inflated is ------->>>> light <<<<-------- enough so that the balloon's average density is lower than that of air - same reason a metal ship floats.
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Using a weight difference to point out that it's not a weight difference is not good form. :sly:

Nit-picky, but I can concede that it's lighter because it's less dense, which is what makes it bouyant. Still, in general discussion of helium balloons, dirigibles, blimps, etc., they are "lighter-than-air" craft.
 
At rest, there is 1 G of force on a car and it's contents. The helium balloon floats in the car due to it's lower density. If you start accelerating, you now have Gs pulling back on the car, and the helium balloon will move forward, against the force, just as it does with gravity pulling on it. I have tried this before, and it does happen.
 
That was really nitpicky, wfooshee. I struggle with the English equivalent of some scientific terms, and light was such a mistake...

Still, the reason is not being actually lighter - but that it moves forward because the air-density isn't equal, theoretically, in the car, and hence it moves to the place of lower density.
 
It was meant in jest (with a smiley and everything), and I apologize if you took it wrong. But I finished by agreeing with you. . . .

Not having actually tried it to see what happens, I still would think the balloon behaves inertially, i.e. moves back on acceleration, but Minicooper says he's done it and it goes opposite, so I defer to the actual experimenter who's observed the phenomena. I'm using the Greek philosophy method, just thinking about it, not the scientific method of actually trying it.
 
Actually, if you just think about it, logically, helium should go backwards inside a sealed vehicle under braking.

Helium is lighter than regular air. A taut helium balloon floats because the weight for the volume of helium inside is still less than that of the air around it. Note, a helium balloon does not need to be full to float... it just needs to be full to be pretty.

If the balloon material is strong enough, you can fill a helium balloon to the point where it will not float. Weight will actually increase and the balloon will sink.

As such, a helium party balloon floats because the air inside has less mass per volume than the air outside (density, same thing). Since the air outside is heavier, it will move to the front of the car under braking and in effect, push the balloon backwards by volume displacement.

You can conclude much the same thing about the air in your car from observation. The mass of air does noticeably move forwards and backwards under acceleration and braking... your airconditioner becomes stronger or weaker (if you've got a crappy old blower, like I had in the 626) as you accelerate and brake, as the heavy air moves back and forth in the cabin.
 
ROAD_DOGG33J
Why do music CD's sound better after 1 or more listens?
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The first listen is your judgmental phase where you are critical to determine if you like this new CD.

After that you accept it and don't go into "we fear change" mode.


If you mean quality of fidelity, not quality of taste, then I think you are just imagining it.

If anything it should be opposite.
 
So it appears filling balloons with helium won't be an option here, no one has it...

I was thinking of something simple instead, a flower, a rose or something, what about that?


I'd figure showing up at her door on her birthday with a nice flower would do the job, but I'm not sure about this... Good idea? Or a "No!" idea?
 
I have a bluetooth dongle for my touch and I'm on my second one. Both weren't really cheap (if that's an issue). They both seem to randomly cut out. I'm puzzled as to why this happens. I thought it might be a connection issue on the touch side dealing with movement but when I giggle it nothing happens. Then I thought it was a "range" issue but even from my head to my right pocket it's about 3ft which is well under the max range.

Then there's my Samsung P2 which has bluetooth built-in and I've never really experienced a cut out on it.

Oh and my bluetooth headset is a Plantronics 855 which isn't anywhere cheap.
 
Maybe the BT signal they're producing is not strong enough to get through your pocket?
 
Or maybe you should stop jiggling your dongle (or giggling as you put it (you really shouldn't giggle at your dongle)). ;)

How is the dongle powered? Is it a low battery problem? Is there a loose connection?
 
:lol: oops, at work and not paying attention. Anyway, it's self powered inside the unit. No low batt. No lose connection that I can see.

If I'm on a MT bike ride I have no choice, but to "giggle" it. Although in that case I think I just bike to fast for the signal to reach my ear. :sly:

Looks like this...
dscn0261jy4.jpg
 
It may not be the dongle but the device itself. I have an iPaq Pocket PC whose connector accepts a charger but not a data cable, unless it's held at exactly the correct angle. I gave up syncing it in the cradle (even though it charges in the cradle perfectly) and went to BT to sync, which was slower but more reliable than the flaky data connector.

The only way to be sure is to let a buddy with another touch try your BT piece and see how it goes.
 
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