car thermometers

[argosy]

How do car thermometers work ? In spite of sun, wind chill, warmth from the engine etc., they come up with a seemingly accurate result. I should appreciate the answer.
Many thanks

[rigger_john]

In my car the thermometer is located in the nearside door mirrror, it's an electronic one ( based on a tempreture dependent resistor)

As the mirror is out side of the car but not sealed against the air but protected from direct wind chill and rain ect I think it would just read the air temp directly from the static air that surrounds it

[argosy]

Thanks, rigger_john for your answer. It did not occur to me that the thermometer might not be where the display is ! I shall check tomorrow - too cold and wet to look now

[Hammer]

Wind chill doesn't make things colder anyway. It makes people feel colder because we are warmer than the surrounding cold air and the wind takes our warmth away more quickly. Inanimate objects such as thermometers are not made any colder by the wind.

So all the manufacturers have to do is put the thermometer somewhere away from where all the warm bits of the car are (ie the engine)

[rigger_john]

then why does blowing on somthing hot make it cooler? I would say that a car thermomerter is supposed to measure static air tempreture and I think air moving over the sensor would have a cooling effect.

IMHO

[Hammer]

Perhaps I should have said that wind chill doesn't make things colder **than the surrounding air**

Blowing on hot things makes them cooler because it helps the heat to escape faster.

Blowing on something that is the same temperature as the air around it has no effect. Put a thermometer in front of a fan and it still shows the same temperature.

Check out Q2 here http://www.weather.gov/os/windchill/windchillg lossary.shtml