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Current time:0:00Total duration:6:34

LeBron Asks: Why does humidity make it feel hotter?

Video transcript

LEBRON: Some reason Miami can be hot. I'm told the humidity makes it hotter Why is this? KHAN: Excellent question LeBron. Let's first think about what people are talking about when they even say "humidity" And there's a couple of ways to think about humidity, but typically when you are the weatherman or in everyday talk people say "Hey it's really humid out there." or "It's high humidity." They're talking about relative humidity, and it's usually indicated by a percentage Let's just think about what the different percentages of relative humidity mean. So right over here, we have 0%. So right over here, we have 0% relative humidity. and over at the extreme other hand, you have 100% relative humidity. at any given point, the air is some place between 0% humidity and 100% relative humidity. at 0% relative humidity is essentially saying that there is no water vapor in the air or non-measurable amount of water vapor in the air. As we go to this molecular view of what it might look like little water droplet maybe on our surface of our skin So just to be clear, these are the skin molecules - not even skin cells, which will be the actual skin molecules. Let's just simplified them as brown circles. And this right over here - this is the actual water molecules. So these are water molecules And maybe is a drop of sweat, or little water that got dropped on our skin and it is in liquid state you have this hydrogen bond between the molecules that are super strong so allows these molecules to slide pass each other and that's why liquid flows the way it does. And we've already talked about why sweat makes you cooler but warm up you a little bit. Captions by Isaac@RwmOne (youtube.com/RwmOne)