相そう対たい速そく度ど

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Meanings

1

noun

relative velocity

Physics term: the velocity of an object as observed from another moving object or reference frame.

相inter-, mutual, together

対vis-a-vis, opposite, even

速quick, fast

度degrees, occurrence, time

相そう対たい性せい理り論ろん
Theory of relativity; a broader concept in physics, while 相対速度 refers specifically to the velocity between two objects.
速そく度ど
General term for velocity or speed; 相対速度 specifies velocity relative to another object.

Compound of 相対 (relative) + 速度 (velocity).