Why, if cold is the absence of heat, do you feel cold air rushing out of a house when you have the door open?

Question

Shouldn't you feel hot air rushing in?

Answer 1

Your understanding of cold/heat is correct, but in the situation you described, you are feeling air. Air rushes out from area of higher pressure to lower. If the air is cold (holds less heat), then you feel that air.

Also, when seal is broken (ie. door is open), air from two side migrates into each other - no pressure difference is required.

If you were to be standing on the other side, you DO feel heat heat coming in. I live in Florida. I feel this everyday.

Answer 2

I think what you are trying to get at is that if heat always flows from hot to cold, why does it seem like the cold is flowing. While it is true heat only flows one way, we will need to keep in mind that heat must be transmitted through a material (not considering radiation which is not technically heat, but thats another discussion).

So if all the air was stagnant with no movement, you would not feel a cooling, but a very slow gradual warming. Since the air is free to move around, you are most likely feeling the cool air from inside the house rushing out past your legs. However, if you placed your hand at the top of the door frame, you would most likely feel warm air rushing in.

The two phenomenon going on here are pressure differentials from the air conditioner fan pressurizing the house, and the cooler air being a little more dense than the warm outside air, causing slightly greater pressure at the floor level. The other thing going on is that there may be a slight wind chill from the 'rush' of air increasing the cooling rate on your skin. Opening the refrigerator door would probably give a similar experience.

However, if there was a stiff wind blowing, open a window on the opposite side of the house, then open a door or window facing the wind, and you should feel a good influx of warm air.

So you probably don' feel hot air rushing in because the house is pressurized slightly compared to outdoors. Also, that the warm air is going to be lighter than the cool air, the warm air will generally immediately rise and you wont feel it right away if you are standing back from the door.

Answer 3

Cold air is heavier than warm air... so you feel the cool air rushing out while the warm air rushes in over your head.

Answer 4

verify the outdoors of the residing house windows the place the flashing is going around the residing house windows (assuming which you have siding on your place) purchase cans of expandable spray foam at your community ironmongery shop. Fill interior the gaps with the spray foam. Do the comparable subject on the interior for the residing house windows. on your doorways purchase self stick insulation foam it quite is accessible in a roll. carry on with the froth to the doorway so as that once the door shuts all the gaps are closed off. Use a draft dodger around the floor in front of the door to circumvent warmth from escaping.

Answer 5

when you open the door, the air on the bottom of the room is able to move, this is the colder air inside the room ..... the initial "breeze" is the displacement of that cold air from the air outside.... therefore feeling a cool breeze

Answer 6

maybe you do feel the hot air rushing out but like most things in it's a matter of perspective.. example, is the glass half-full or half-empty

Answer 7

Pressure differential. Higher pressure inside causes flow to the lower pressure outdoors.

Answer 8

You feel the absence of heat leaving your place of abode, it's quite normal, the absence of heat probably follows you everwhere, you just don't normally notice

Answer 9

because its cooler in your house than it is outside, and there is more pressure inside your house than outside, so when the door opens, all that pressure releases, and rushes out.