Velocity Measurement in Quantum Mechanics

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How can velocity be measured in quantum mechanics since one can not measeure position without disturbing the particle?
 
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You have to be clever.

You can get momentum from a collision.

You can rig a detector to intercept part of a whole bunch of particles, then do it again in a different place, and use the time between them. You don't get the speed of the particular particles detected but you do get the speed of the bunch.

You can pass a beam through rotating collimators like you do to measure the speed of light.

Short answer: lots of ways.
 

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