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When the position vector r = x i + y j + z k changes sign as - r, which one of the following vector will not flip under sign change?
(4) Angular momentum
r - r
v = d rdt - v, a = d vdt - a, p = m v - p (all flip)
Angular momentum: L = r p (- r) (- p) = r p = L
Angular momentum does not flip.
Answer: (4)
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