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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Yes, but not in the way you might be imagining; it usually involves a large mass/building being at a very cold temperature for several days/weeks. If the weather changes and gets dramatically warmer, the building will be colder than ambient because it can’t absorb enough energy that fast.
I have seen this on large granite faced buildings that have grown a heavy “beard” of frost because the temperature was way below freezing for a time and a warm front brought the temp up to the low 40s.
Sure, there’s a few mechanisms that can reduce an object’s temperature.
A) Radiation. Some objects will radiate particles off of them, which results in the object becoming colder as the most energetic (highest temperature) particles will tend to be ejected first.
B) Insulation. If an object is perfectly insulated at a lower temperature, and the ambient temperature raises, there’s no reason for that object to be the same temperature as ambient. In practice this doesn’t occur, but in principle it works.
C) Failure to absorb heat, such as when in shade or reflective properties. If the general area is being heated by the sun, but the object in question is reflective or shaded, it will tend to be colder than ambient.
D) Evaporation or phase change. When an object changes phases, it uses an incredible amount of energy to do so, decreasing the temperature of surrounding masses. For instance, it takes a significant amount of energy to turn ice into water, as opposed to just heating up water. By exploiting phase changes you can keep an object fairly cool compared to ambient (such as seen in air conditioners)
A good example of when an object might be colder than ambient is outer space; the temperature can actually get quite high, but because it’s a vacuum and there’s no atmosphere to transfer temperature around, you will often see objects that are colder than ambient, as they radiate off a decent amount of energy. In other words, they’re insulated, radiating, and will often fail to absorb heat if they’re manmade, as they will be often painted white or with a reflective material.
No, due to the second law of thermodynamics. Basically, all objects will reach equilibrium. Cold things get hot and hot things get cold until they reach the same temperature.
To be nitpicky, if you observe an object for a time many orders of magnitude over the age of the universe, there is nothing really stopping this from happening.
To put it simply, theoretically yes, an object can get colder (or warmer) than the ambient temperature.
Temperature is a macroscopic property, meaning that it measures the “excitation” (aka the velocities of each particle in a macroscopic way) of particles in a thermodynamic system. More temperature means more excited particles. Particles can get more excited through collitions between themselves. If you put together a cold object and a warm one, yes, theoretically the colder could get even colder and the warmer could get even warmer (though the average temperature will remain since temperature is directly related to the energy of the system in an 0-energy loss environment).
But why does it never happen??? That is where statistics come in. In a system of 1 gram of water there are 0.33 times 10 to the 24th power (or something like that) particles of water. So if you put a single gram of water heated up to 20 degrees next to a single gram of water heated up to 2 degrees, yes, it could be that the temperature of the warmer could get to 30 degrees so long as the temperature of the cold one drops to -8 degrees. But it doesn’t happen because it’s more likely that when two mollecules of water collide, the faster one imprints some of it’s velocity to the slower one. This usually depends on factors like the angle of collition, the direction, the geometry of the mollecules, and a very large set of variables.
Now say that only one in one thousand collitions actually works how we desire, this is, the faster mollecule gets faster and the slower one could get even slower. Now take into consideration the trillions of mollecules in the system and the amount of collitions… Statistically it is impossible that the warmer one could get even warmer. Simply, the odds are not in their favour. That is a very important concept in physics: systems don’t tend to order, but to the statistically most likely state, and that is what enthropy really is. So, when two different temperature objects are next to each other, the most likely state is that they average their temperature. Of course, like I mentioned previously, this does depend on many factors, and we could find materials that “defy” that natural law, but in reality, they are just obeying the laws of thermodynamics.
Thermodynamics can basically be summed up as “heat moves from things at higher temperatures to things at lower temperatures”, with the logical conclusion that generally objects will reach thermal equilibrium at the same temperature if nothing else is actively moving heat around.
In the specific case of an object outside, it is possible to be below the air temperature because as well as conduction, things lose heat by radiation. A clear sky radiates very little heat (because you’re effectively looking out into space which is very cold) so things facing the sky can radiate away their heat into the sky and become colder than the surrounding air.
[This video](https://youtu.be/N3bJnKmeNJY) shows a special paint that radiates heat effectively to let an object become cooler than the surrounding air if it’s under a clear sky.
Yes and no.
A object with no active cooling system that’s switched on and running? No.
An object with a cooling system, like a refrigerator or a freezer? Yes.
If your car is switched off and just sitting in the ambient air, it will always be at or close to the temperature of that ambient air.
Others have explained why things feel hotter/colder to us despite being similar temperatures.
E.g. metal at 20c will feel colder than most plastics at 20c.
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So this is a tricky question. I’m guessing you obviously aren’t asking “can thus ever happen at all?”- because I’m guessing you’rr will aware of air conditioners.
Now… Are you asking if something like that can happen without the use of electricity?
Yes. Turn a can of compressed air upside down and use it. It’ll turn super cold.
Now, are you asking if something like this can happen without animal interference? That I’m not sure of… Maybe an endothermic reaction might occur if a rock of some sort falls into a chemical pool of some sort. Or the right two gasses meet.
Plenty of scientific answers below which I’m sure are correct but for a simpler answer, I believe temperature is transferred more through solids than the air. This is why objects can feel colder to the touch than the air around them, for example someone’s hands can few colder than the air they are in but they probably aren’t
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