Assertion: acceleration's unit | /r/HasProperty | \displaystyle \hat u}}_{r}(t
Facets:
Source sentences:
text: The unit vector u ^ R ( t ) {\displaystyle {\hat {u}}_{R}(t)} has a time-invariant magnitude of unity, so as time varies its tip always lies on a circle of unit radius, with an angle θ the same as the angle of r → ( t )