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In physics the speed of light is the fastest something can travel, but what...

is there a slowest speed something can travel whilst being in motion?
Original post by Highrise769
is there a slowest speed something can travel whilst being in motion?

Speed of bullet
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Original post by Highrise769
is there a slowest speed something can travel whilst being in motion?

Well (near) absolute zero particles have almost no KE so their speed will negligible. The closer you get to absolute zero the less KE the particle will have, so it's speed will get closer to zero so there's not really a minimum non-zero speed.
Speed of radio waves
Original post by NewtoTSRR
Speed of radio waves

Radio waves move at the same speed as light!
Speed for an object with mass can approach 0 (relative to nearby objects, a molecule at near rest on Earth is still travelling around the sun with a speed). Massless particles like light (photons) must always travel at the speed of light, no matter what.
At a fundamental level, the speed will be constrained by the uncertainty principle. If the speed is zero, then momentum is zero, but that means we must have infinite uncertainty on the position of the particle so is no good. You can strike a balance between the two to get some sort of lower bound on the momentum of a particle.

For macroscopic objects, you can ignore quantum mechanical effects and so a macroscopic object could probably move indefinitely slowly, though even in a solid all of the atoms are vibrating in the lattice all the time (and you can't reach absolute zero so you can never get them to be completely stationary, and even so I think I remember learning that electrons would still move at absolute zero because of the uncertainty principle (or perhaps this is part of the argument as to why you can't reach absolute zero))

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