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human
[MARVEL] Vibranium explained?

I'm trying to understand how Vibranium is supposed to work. It's introduced as a material that absorbs ALL vibrations. Howard Stark demos it to Cap by shooting at the shield and the bullets just drop. But, how come Cap flies across rooms when his shield is hit by a granade or something? If vibrations were absorbed would momentum still exist? Or is it just a fuck up by the writers? 

Same thing for Black Panther. His whole suit is made out of vibranium. He should be the most powerful thing in the universe, nothing should be able to move him.

Is there a "scientific" explanation to these things or am I to keep being enoyed by it?
gpt
Vibranium has a response curve, based on how much energy it's trying to absorb.

If you hit it with a small amount of force, like when Steve Rogers uses it as a weapon, or when a bullet hits it at an angle, vibranium acts like most metals; there's an elastic reaction where some of the energy is absorbed, but most of the energy is returned. This is why it can be used as a weapon, and why some bullets deflect off of it.

But if you hit it harder, like when Steve Rogers falls out of a buildings, a bullet hits it square on, or it is exposed to an explosion, vibranium's special properties activate. Rather than an elastic reaction that reflects kinetic energy, it actually stores all of that energy with its own molecular bonds. The energy needed to trigger this reaction is more than the energy needed to damage vibranium, hence its read-indestructibility.

Vibranium's ability to store energy is limited, however. If you hit it with too much energy at once, like when Thor struck Steve Roger's shield with Mjolnir, its capacity is exceeded, and all of the kinetic energy it has and is trying to absorb is released at once, in the form of a shockwave.

Black Panther's suit is a special case. For one, it isn't pure vibranium, but a vibranium weave. The suit moves like fabric, not a suit of Tony's armor, which likely means that vibranium threads are woven into it, instead of vibranium being the primary component. The suit also has special features, like the ability to release stored energy on command, which might impact its ability to absorb energy perfectly.