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# VERY IMPORTANT: Prove my dad wrong - thermodynamics? watch

1. (Original post by Stonebridge)
It's all about convection currents. A number of posters have stated this. The diagram here shows what could happen. With both the door and window open, the rest of the house will still be cooled by the draught from the window. The point is that your room is not at an even temperature. The air temperature near the floor (with window open) is cooler than the air near the ceiling. And, more importantly, if this air is cooler than the air in the next room (which it is on your graph) then this cooler air will also flow into the next room. The warmer air in the next room will have to flow out to make way.
The diagram is a vertical section with your room on the left, the door in the middle. Warmer air near the ceiling. Cooler nearer the floor.
[]http://i57.photobucket.com/albums/g220/DrNebula/convection.png[/IMG]
why would warm air flow into the hot room ( the orange arrow, top pic )? Because of pressure rather than temperature differences? (i.e. drawn in). Wouldnt hot air from my room go into the corridor too as well as outside?
2. Have you considered that some air from outside can blow straight through your room to the door fast enough so that they are still below the temperature of the rest of the house??????????????????????????? ???????????????????

You have over-simplified it.
3. (Original post by Stonebridge)
It's all about convection currents. A number of posters have stated this. The diagram here shows what could happen. With both the door and window open, the rest of the house will still be cooled by the draught from the window. The point is that your room is not at an even temperature. The air temperature near the floor (with window open) is cooler than the air near the ceiling. And, more importantly, if this air is cooler than the air in the next room (which it is on your graph) then this cooler air will also flow into the next room. The warmer air in the next room will have to flow out to make way.
The diagram is a vertical section with your room on the left, the door in the middle. Warmer air near the ceiling. Cooler nearer the floor.
This doesn't apply if the air blowing in has any speed, which of course it does.
edit: even if it did, you have made an incorrect conclusion.
4. If your room really is hotter than the rest of the house, then in order for your situation to cause the house to cool down, heat would have to move from the cold house to your warm room before leaving through the window. That is against the rules.
5. Say that the cold air and warm air from your room flows out of your room into the rest of the house. Doesn't the air flow make it feel cooler?

Eg.
Temp - 30C No air flow - would feel like 30C
Temp - 30C Air flow - makes it feel like 25C?

Even though the heat isn't escaping, by opening your door, you are making the house "feel" colder?

Same principle as electric fans, you are just blasting the warm air around.

By closing the door, you restrict/stop the air flow.
6. (Original post by jj193)
This doesn't apply if the air blowing in has any speed, which of course it does.
edit: even if it did, you have made an incorrect conclusion.
Could we have your considered analysis then?
If the cold air was "blowing" in, the effect I've described would be even greater.

Which laws of physics are you using to justify your conclusion?
7. (Original post by cowsgoquack)
why would warm air flow into the hot room ( the orange arrow, top pic )? Because of pressure rather than temperature differences? (i.e. drawn in). Wouldnt hot air from my room go into the corridor too as well as outside?
If the cooler air on the floor of your room is cooler than the air in the next room, it will flow in there.
If it does, then air from higher up that room must flow into yours.
It all depends on the temperature of the air on the floor of your room being lower than in the next room.
The temperature of the air outside is cooler than the air in both rooms according to your graph.
8. (Original post by Bobifier)
If your room really is hotter than the rest of the house, then in order for your situation to cause the house to cool down, heat would have to move from the cold house to your warm room before leaving through the window. That is against the rules.
No because the rooms are not at a uniform, even temperature from top to bottom or left to right. That's why convection takes place. See my diagram.
9. (Original post by Stonebridge)
Could we have your considered analysis then?
If the cold air was "blowing" in, the effect I've described would be even greater.

Which laws of physics are you using to justify your conclusion?
Convection doesn't happen like that, it gets distorted so instead of up and down drafts they are slanted etc. (Consider momentum)

By your same logic of air 'convecting' through the room and out the door, we reasonably know that there is a general flow of cold air into the room from the window. So it is fair to say air is blowing in, i.e. a draft.

I'm not going to offer an explanation/answer because there are too many assumptions that would need to be made, and I couldn't even if I wanted to. I can only appreciate that you are wrong.

From experience:
The temperatures in the room and the flows of air are not spread evenly *you appreciate this in the above post ffs!*. For example think of a room where the door and window are close and opposite and it is very wide. From experience I feel that alot of the air goes straight through the room and into the house. Alternatively we have a HUUUUUUUUUUGE room and/or a slow draft, your conclusion may be correct.

You don't use physics to tell someones experience doesn't happen. Thats the law.
10. (Original post by jj193)
Convection doesn't happen like that, it gets distorted so instead of up and down drafts they are slanted etc. (Consider momentum)

By your same logic of air 'convecting' through the room and out the door, we reasonably know that there is a general flow of cold air into the room from the window. So it is fair to say air is blowing in, i.e. a draft.

I'm not going to offer an explanation/answer because there are too many assumptions that would need to be made, and I couldn't even if I wanted to. I can only appreciate that you are wrong.
That's very convenient.
From experience:
The temperatures in the room and the flows of air are not spread evenly *you appreciate this in the above post ffs!*. For example think of a room where the door and window are close and opposite and it is very wide. From experience I feel that alot of the air goes straight through the room and into the house.
So you agree with me that the house will be cooled (=lose heat)
Alternatively we have a HUUUUUUUUUUGE room and/or a slow draft, your conclusion may be correct.
We were not talking about a huge room. We were talking about the OP's room.
So what, exactly, is your conclusion? Does the inner room cool down when the window is open? You seem to be agreeing with my conclusion that it is, yet telling me at the same time that it's wrong.
You don't use physics to tell someones experience doesn't happen. Thats the law.
Your experience will always be governed by the laws of physics. If it isn't, you're possibly mistaken.

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