Air is weightless
No.We are not conscious of air's weight because we are immersed within it. In the same way, even a large bag of water seems weightless when it is immersed in a water tank. The bag of water in the tank is supported by buoyancy. In a similar way, buoyancy from the atmosphere makes a bag of air seem weightless when it's surrounded by air. One way to discover the real weight of air would be to take a bag of air into a vacuum chamber. Another way is to weigh a pressurized and an unpressurized football. A cubic meter of air at sea-level pressure and 0C temperature has a mass of 1.2KG. The non-metric rule of thumb says that the air that would fill a bathtub weighs about one pound. Here's a simple way to detect the mass of air even though the air seems weightless: open an umbrella, wiggle it slightly forwards and back, then close it and wiggle it again. When you wiggle it when open, you can feel its increased mass because of the air the umbrella must carry with it. (Ah, but then we must explain the difference between weight and mass!)
No.We are not conscious of air's weight because we are immersed within it. In the same way, even a large bag of water seems weightless when it is immersed in a water tank. The bag of water in the tank is supported by buoyancy. In a similar way, buoyancy from the atmosphere makes a bag of air seem weightless when it's surrounded by air. One way to discover the real weight of air would be to take a bag of air into a vacuum chamber. Another way is to weigh a pressurized and an unpressurized football. A cubic meter of air at sea-level pressure and 0C temperature has a mass of 1.2KG. The non-metric rule of thumb says that the air that would fill a bathtub weighs about one pound. Here's a simple way to detect the mass of air even though the air seems weightless: open an umbrella, wiggle it slightly forwards and back, then close it and wiggle it again. When you wiggle it when open, you can feel its increased mass because of the air the umbrella must carry with it. (Ah, but then we must explain the difference between weight and mass!)
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