Ok. on a cold winter day when you exhale, it looks like steam is coming out of your mouth... the same is true for your car. In the winter when you go outside and warm your car up in the drive way at first when the engine is "cold" a whole bunch of steam is coming from the exhaust and it starts to cloud around the car and the driveway... but then as you start to drive it, or the engine has "warmed" the steam only seems to come inches out of the exhaust. I dont understand. If the air coming out is warmer... wouldn't that make more steam. This does'nt make sense to me. Does anyone know why?
2007-03-23 22:23:44 · 4 answers · asked by dcquin31 2 in Science & Mathematics ➔ Weather
sorry if im wrong but i do believe that it is because as the car is beggining to warm up it is working harder, creating more heat, once it reaches there it has to work less to keep its self running.
2007-03-23 22:29:19 · answer #1 · answered by Anonymous · 0⤊ 1⤋
Water is a by-product of combustion of hydrocarbons (the hydrogen and oxygen form water vapor). When the engine is cold, the vapor cools as it leaves the engine, as the tailpipe and other objects are cold. This causes the vapor to condense out of vapor into water droplets.
As the engine heats up, the vapor is warmer and the tailpipe and other parts are warmer. This allows the water vapor to remain as a gas, at least until it naturally cools.
To demonstrate this take a warm engine where you can't see the vapor and hold a glass of cold water in the exhaust stream. Droplets will immediately form on the glass.
2007-03-23 22:41:09 · answer #2 · answered by Matthew P 4 · 0⤊ 0⤋
The steam is caused by the condensation that has accumulated in your car's tailpipe while it wasn't running. As that condensation burns off, there's less and less moisture to turn into gas (steam).
2007-03-23 22:32:33 · answer #3 · answered by Anonymous · 0⤊ 1⤋
actually there is no relation between steam coming out from the mouth and the steam from exhaust of your car. First you should know that fuel that is present in your fuel tank requires ignition temp to burn. Int he winters since the temp is not sufficient to raise the temp of fuel to its ignition temp there fore burning process is not complete hence unburn fuel in the form of carbon comes out whose colour is dark. it dissappears as it is dispersed in the outer air. when temp becomes sufficiently high burning is complete and only colourless gases are evolved.
2007-03-23 22:37:47 · answer #4 · answered by vij 2 · 0⤊ 2⤋