If I open the windows in my room, which has AC turned on and it’s cool in the summer, it will quickly become as hot as it is outside, why isn’t it happening around the globe?
In: Physics
Because air does not move as fast as the Earth rotates.
Consider a stupidly simple setup –
If air to be moving at 500 km/h (imagine the wind), it would take about 3 days for it to go around the Earth. In those 3 days, the Earth has rotated thrice…so the heating from the Sun has changed it direction three times. So before the air temperature cam equalize the heating has shifted to another side.
Its like you keep moving your heater or AC to different parts of the room before the air can actually circulate and reach a constant temperature all over.
Of course, air doesnt move at 500 km/h , and a lot more complicated stuff happens – land heats up faster than the sea, the earth is tilted depending on season etc. All this makes it even mlre impossible to reach a constant temperature .
ELI15: This is why whether is a ‘dynamic/chaotic’ system. Energy us being fed to the system ‘anisotropically’ faster than the system can ‘equilibrate or reach a steady state’.
Your room is a small. Maybe 10 metres across. Even air moving at 10 metres/h (your walking speed is about 5000 m/h) would completely exchange with the outside within an hour. But even it doesnt really have a constant temperature if AC / heater is on. The air close to the device is hotter/ cooler. It just moves around quickly enough for you to not notice the tiny difference in temperature if you open the room.
Latest Answers