The force of the air

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Q1: How does a hovercraft work?

[Answer]

Air is a thin substance that doesn't have as much buoyancy as water. But if an object moves quickly through the air, then the air cannot get out of the way fast enough and it acts as a force working against movement. This is why fast-moving things need streamlining.

Of course, if you want to use the air as a brake, you design something that will hold on to air – a parachute, for example.