What is the approximate maximum speed reached by the material ejected during a supernova explosion?

Answer

Up to 10% of the speed of light (roughly 30,000 km/s).

The explosion ejects material, known as ejecta, at speeds that can reach as high as 10% of the speed of light, which is quantified as approximately 30,000 km/s.

What is the approximate maximum speed reached by the material ejected during a supernova explosion?
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