Say you store a vehicle outside all winter, if there was an usually cold week, say -20 degrees Fahrenheit for example, is it possible for the car to be colder than the -20 since it sat weeks prior to the -20 temps?
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With a few exceptions, the car can only ever be as cold as the environment
The same is true the other way too, if you put food in an oven and the oven is set to 200, the food (or any object in the oven) can never be hotter than 200 no matter how long it is in there
There is a small note that it can take time for heat or cold to penetrate. So to use the food example the middle of the food can remain colder than the temperature of the oven for a short while until the heat in the air of the oven manages to have an effect on it, which takes time. Similarly, if you park your car outdoors, and it’s -20, it’s going to take a while for the centre of the car to actually reach -20 if it was warmer than that before because you were driving it (or it was previously parked indoors).
Also, with enough insulation you can increase that time to penetrate, but’s based on a curve with time and temperature difference. The speed depends on how well the material conducts or resists heat
No. See the first and second Laws of Thermodynamics which has to do with the conservation of energy, that energy may be transferred from one object to another, and converted from one form to another, but cannot be created nor destroyed, and of gradients of energy which drives transfer from areas of high to areas of low
When the car is parked, and it is warmer than the ambient air around it, some energy in the car is stored as heat, and is relatively higher than that of the ambient air around it. Some of the heat energy of the car is transferred to the air and warms the air (effectively dissipating it since the air is almost infinitely attached to all the other air) until the car and the ambient air are at the same temperature at which no more exchange occurs.
Maybe if a hot wind suddenly blew through. But generally those temperature changes are gradually and stuff outside wouldn’t have much lag time in matching the temperature. Certainly not over a course of weeks. If you parked your cold car in a cool garage sure. Otherwise no.
The car seat no.
But in a more general sense, yes. Many things other than ambient temperature can influence the temperature of a substance, one of which is harnessed by the refrigeration cycle to power air conditioning systems. If you have a refrigeration system shut off for a long amount of time, it will eventually match the ambient temperature, including the refrigerant. But as soon as it starts running, the refrigerant is compressed, raising its temperature, which allows the energy to leave it before it is allowed to expand again, leaving it much colder than it was originally (which matched the ambient temperature at first).
A more simple example of the same principle: cans of compressed air. As you use them, they will get colder, even to the point of freezing water vapor from the air.
Things can *definitely* cool past ambient temp, with strings attached. The manner in which heat is lost plays the key role, and the item will not stay cooler once the process stops.
One way (in open air) uses water as a mediator. Dry warm air pulls water off of warm thing – and some of the heat with it. We used this out in Afghanistan to cool our water and whatever else. Put drinks in socks, tie to something (preferably a vehicle) wet sock down, move around. After about a 10min drive our 130°f water was actually *cold* and it took maybe ¼ bottle of water to sufficiently cool.
Another way (relevant link below) is by converting heat to EM radiation (light), infrared, in this case. Our atmosphere captures most of that but there is a band which isn’t recaptured by the gasses. Converting heat to this particular wavelength allows it to shoot off into space and be completely lost to the planet (but not the universe).
No, but yes, but no.
No, because all forms of heat transfer depend on the difference in temperature between two materials. If you have a hot rock at 60C and a cold cup of water at 5C and you put the rock in the water, it will warm the water up and the water will cool the rock down until they’re both at exact same temperature, somewhere in the middle.
If two objects are at the same temperature, no heat transfer can occur between them.
Yes though, because there’s some exception due to the “latent heat of vaporization”, particularly of water. When water evaporates, it needs extra energy, which it *loves* to steal from its surroundings, particularly the things its in contact with. This is how sweating works, and it’s why sweating can help you cool down even when the air is hotter than your skin. The water evaporates into the air, and because of its “latent heat of vaporization”, it steals a bit of energy from your skin, cooling you down. This only works if the relative humidity is below 100%. This can cause a object that’s wet to get colder than its surroundings, but it’ll only last until the water is done evaporating. This is called the evaporative cooling effect. On a small scale, you can find what are often called “swamp coolers” which blow air over a water soaked surface to cool the air. These drive up the humidity while cooling though, and can cause a higher humidity in the space making it feel even *more* uncomfortable in the long run. They also have a nasty tendency to get moldy. Hence the name “swamp cooler”. On a large scale, industrial cooling towers use evaporative cooling, and are used to cool water for industrial processes, and can lower the temperature of the water to below the atmospheric temperature, so long as it’s not 100% humid out.
But practically, and in your scenario, no.
The evaporative cooling effect wouldn’t have much effect below freezing because any standing water would freeze anyways. Ice and snow can still sublimate and steal energy, but that is WAY slower than evaporation, and would have a completely negligible effect.
One object can *feel* colder than another, but that’s related to how quickly they transfer heat away from you. You can have a piece of wood and piece of aluminum at 10C and touch them. The aluminum will *feel* much colder. Your skin (36C) has the same temperature difference with each, but aluminum conducts heat much better than wood, so it’s able to take that energy from your skin much faster. Fun fact, your skin doesn’t feel temperature, it feels *heat transfer*. That’s why when you come inside with cold numb hands, you can run them under cool tap water and it will still feel burning hot. Your fingers are colder than the water, and you’re feeling that fast heat transfer into your body and it feels the same as burning your fingers.
Um, not enough information given to give an exact answer.
Things can lose or gain heat from temperatures around them.
If you happen to be implying the prior temperature the day before always -30° for at least a short time the car *could* be colder.
I’m going to guess though that something like -20° was in the news and your car has a display that read -25° or something.
A
I’ve noticed that it seems like car temperature displays are often lower that the local forecast.
Things like where this sensory is in the vehicle end up mattering because there is always a slight variation to immediate local temperature and an area average even down to such a “local” as an individual particle compared to it’s neighbors. It’s just not going to have the *exact* energy of them in any system (based on relative or scale) where energy can be lost or gained anything outside of that group of measurements. And the laws of entropy having equalized it all yet.
Plus factors like wind, moisture, shade (which can vary a temperature by 20° in many conditions pretty easily)
Hopefully I answered the actual question
There are a couple of things at play here…
the first is Newton’s law of cooling, which means that all objects in an environment will eventually reach the same temperature. The thermal mass of an object and the temperature difference play a large part in how long that takes – and it works both ways. An object that’s been sitting in a cold environment for an extended time will be colder than a warmer surrounding environment for a period of time until it reaches equilibrium.
The second is perception – when you touch an object that has significant thermal mass and is colder than your body temperature, it will immediately begin absorbing heat energy from your body – which makes it feel colder. You are at the same time warming that object up a very small amount.
Your asphalt roof of your carport probably gets colder than ambient on most cloudless nights. Black body radiation is a thing and that dark roof with no heat source underneath will probably continue to radiate energy.
Here is how people used to create ice in above zero conditions for thousands of years.
https://www.realclearscience.com/blog/2018/07/09/how_people_created_ice_in_the_desert_2000_years_ago.html
So the answer is absolutely yes objects can get colder than ambient.
Assuming you are talking about just sitting there without using refrigerants..
For a five year old .. generally no..
There’s no such thing as cold actually, there’s only the absence of heat..
So conceptually the heat has to go somewhere else to get something cool.. you cant add cold to something, you can only take heat away.
If that makes sense then the car will be about same temp as surroundings because temperatures try and normalize.. the heat likes to spread itself around and even out ..
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