💨 Kinetic Theory — pressure and temperature emerge from molecular motion

A gas is an enormous number of tiny molecules flying about in incessant random motion, colliding elastically with each other and the walls. Their drumming on the walls is the pressure P; the mean square of their speed fixes the temperature T. Raise T or pack in more molecules N and the walls feel more pressure.

Walkthrough 1 / 3

A gas is a box full of molecules in incessant random motion — the teal beads fly and bounce off the walls.

Temperature T 300 K

Number of molecules N 30

P = ⅓·n·m·<v²> · v_rms = √(3RT/M) (N₂ gas)
P = — kPa · T = — K · v_rms = — m/s

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