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Subject: Physic 求教


Author:
不要CY
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Date Posted: 23:33:01 07/05/12 Thu

A particle of dust is bombarded by air molecules and follow a zigzag path at constant speed v.

Assuming each step has a length d, what is the length of a displacement vector after N steps where N is large? Assume each step is taken in a random direction on the plane.

ans: d times root N

Why?

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