Air Inside Bus: Common Phenomenon Explained

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The discussion revolves around the phenomenon of air movement inside a moving bus, particularly when windows and doors are closed. Participants explain that the bus is not airtight, allowing air to enter and exit through gaps around doors and windows. The apparent air movement is attributed to inertia, where air molecules lag behind as the bus accelerates, creating a pressure gradient that pushes air from the front to the back. This effect can occur even in a sealed bus, leading to experiences of air being sucked in or out of windows. The conversation highlights the complexities of air dynamics in vehicles, emphasizing that both acceleration and constant velocity can influence air movement.
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My doubt is reguarding the common phenomenon observed in the moving bus...While moving in a accelerating bus we all observe the wind gushing inside the bus may it be from the window of the driver or the passenger or even from the doors. My question is if all this air is entering inside the bus from where they are going out if the rear window is closed
and even roofs are packed
 
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hi there blizz

as you have observed, the bus isn't exactly airtight. There may be a temporary increase in air pressure but I would doubt that it last long
There's likely to be as many gaps around doors etc letting air out as there are letting air in

cheers
Dave
 
Hi davenn

If its the door u r talking about then won't u think if a person standing there would experience air entering the bus.
 
Blizz91 said:
if all this air is entering inside the bus from where they are going out if the rear window is closed
Sometimes air is coming in and out thought different parts of the same opening: You feel air coming in from at back of the window, but at its front part a piece of paper gets sucked out of the car.
 
Actually the apparent air movement would even happen in a completely air-tight bus. As the bus begins to move, the air molecules tend to lag due to their inertia. As a result, there is a net movement of air from the front to the back of the bus. This builds up a pressure gradient, that will eventually push the air inside the bus to catch up, and the pressure evens out. The air is sloshing back.

Here is a good demonstration :D.
 
borisgred said:
Actually the apparent air movement would even happen in a completely air-tight bus. As the bus begins to move, the air molecules tend to lag due to their inertia. As a result, there is a net movement of air from the front to the back of the bus. This builds up a pressure gradient, that will eventually push the air inside the bus to catch up, and the pressure evens out. The air is sloshing back.

Here is a good demonstration :D.
I'm sorry, but that isn't the phenomena being described here. If the air temp is constant and absent a void such as created by the balloon, the "sloshing" is miniscule.
 
A.T. said:
Sometimes air is coming in and out thought different parts of the same opening: You feel air coming in from at back of the window, but at its front part a piece of paper gets sucked out of the car.


Ok then, now consider a bus with a large window where a single window is shared by 2 consecutive seats( in a row) then if what u r saying is true then don't u think the passengers sitting they would experience opposite phenomenon but I personally hav experienced the opposite
 
borisgred said:
Actually the apparent air movement would even happen in a completely air-tight bus. As the bus begins to move, the air molecules tend to lag due to their inertia. As a result, there is a net movement of air from the front to the back of the bus. This builds up a pressure gradient, that will eventually push the air inside the bus to catch up, and the pressure evens out. The air is sloshing back.

Here is a good demonstration :D.


hey Boris, I think u didnt get what i asked though there might be inertia of the air particle present there but as russ said I think that effect will be too minuscule and also this is due to bus accelerating, but the phenomenon which I described can be experienced even when bus is moving with constant velocity
 
Blizz91 said:
I personally hav experienced the opposite
And I personally have experienced stuff being sucked out of the car window many times. Sometimes sucked out from the front window, and return back into the car though the back window. With a single opened window the same is possible, just within a smaller opening.
 
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