When we turn our face towards the sun on a day with clear skies: Is the heat we feel on our skin actual heat radiation from the surface of the sun or do we just feel the warmth of the molecules in our atmosphere which have been “warmed” by radiation from the upper atmosphere?
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Look up “three modes of heat transfer,” and you will learn about convection, conduction, and radiation. More than one at a time can be relevant. First part of your question I would say yes, radiation from the sun can be felt on your face, easily evidence by holding up an object to block the sun and you will instantly feel cooler- too fast to be explained by air movement. As to the second part, also yes. We feel warmth transferred to our face by warm air even when we can’t see the sun. Both modes can transfer energy to us in the form of heat.
Look up “three modes of heat transfer,” and you will learn about convection, conduction, and radiation. More than one at a time can be relevant. First part of your question I would say yes, radiation from the sun can be felt on your face, easily evidence by holding up an object to block the sun and you will instantly feel cooler- too fast to be explained by air movement. As to the second part, also yes. We feel warmth transferred to our face by warm air even when we can’t see the sun. Both modes can transfer energy to us in the form of heat.
When you turn to face the Sun, the heat you feel is unobstructed radiation from every part of the whole body of the star – even from the surface on the further side pointing away from you. As it strikes your skin it has been reduced in intensity by the distance and partial blockage caused by the gaseous constituents and the solid particles in the atmosphere. If you could be on the Moon without a space helmet you would feel the same but much stronger heat as there is about the same distance from the Sun but less blocking matter as the radiation covers that distance.
When you turn to face the Sun, the heat you feel is unobstructed radiation from every part of the whole body of the star – even from the surface on the further side pointing away from you. As it strikes your skin it has been reduced in intensity by the distance and partial blockage caused by the gaseous constituents and the solid particles in the atmosphere. If you could be on the Moon without a space helmet you would feel the same but much stronger heat as there is about the same distance from the Sun but less blocking matter as the radiation covers that distance.
From a pasty white boy; I’ve been in a 140°F oven, and I’ve experienced 100°F+ outside temps. The oven, where only hot air is warming, just feels warm, whereas sunlight, even on cooler days, seems to almost sting. Also, if you sit in front of a window on a sunny day, you’ll feel warmer than the ambient air. Based on that, I would assume a fair bit of the heat you feel from the sun would be the sun’s radiation directly warming your skin.
From a pasty white boy; I’ve been in a 140°F oven, and I’ve experienced 100°F+ outside temps. The oven, where only hot air is warming, just feels warm, whereas sunlight, even on cooler days, seems to almost sting. Also, if you sit in front of a window on a sunny day, you’ll feel warmer than the ambient air. Based on that, I would assume a fair bit of the heat you feel from the sun would be the sun’s radiation directly warming your skin.
So many wrong answers here. You get hit bit UV radiation, aka really fast energetic light packets. Those absorb into the atoms of your translucent skin/tissues, do some damage to the molecules, and the rest of the energy gets emmited back as light and infrared light.
You can see the light reflected back in your skin color by your face being lit.
You feel warm because you emit infrared light which is heat.
Beyond that the heat loss creates a thin blanket of hot air next to your skin, and the sensation of warm or cold is in relation to that air, so when you blow on your hand you feel cold for example.
Alternatively you know the answer is UV and not hot air because the sun is so far away the entire day hemisphere is heated by it so everything is pretty much uniformly heated around you, except for shadows and the winds those create.
The sun’s radiation that comes in contact with us is infrared, visible light and uv. any shorter wavelengths either don’t make it or are blocked by the ozone layer.
the infrared that comes into contact with neural receptors in the skin is what causes the feeling of warmth. Infrared waves are a byproduct of heat, so they are it’s indicator as well.
you know how when you heat metal it gets to a point where it starts glowing ? that’s the heat of the metal reaching a point where the electromagnetic wavelength that’s released gets shorter, going from infrared to visible light.
So many wrong answers here. You get hit bit UV radiation, aka really fast energetic light packets. Those absorb into the atoms of your translucent skin/tissues, do some damage to the molecules, and the rest of the energy gets emmited back as light and infrared light.
You can see the light reflected back in your skin color by your face being lit.
You feel warm because you emit infrared light which is heat.
Beyond that the heat loss creates a thin blanket of hot air next to your skin, and the sensation of warm or cold is in relation to that air, so when you blow on your hand you feel cold for example.
Alternatively you know the answer is UV and not hot air because the sun is so far away the entire day hemisphere is heated by it so everything is pretty much uniformly heated around you, except for shadows and the winds those create.
The sun’s radiation that comes in contact with us is infrared, visible light and uv. any shorter wavelengths either don’t make it or are blocked by the ozone layer.
the infrared that comes into contact with neural receptors in the skin is what causes the feeling of warmth. Infrared waves are a byproduct of heat, so they are it’s indicator as well.
you know how when you heat metal it gets to a point where it starts glowing ? that’s the heat of the metal reaching a point where the electromagnetic wavelength that’s released gets shorter, going from infrared to visible light.
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