Soal momentum dan impuls Tolong bantuin jawab yah teman2 kaka2

dik : Pa = MV ; (Pa)' = -3MV
dit : ΔPb = ...???
jawab :
*) hukum kekekalan momentum :
P = P'
Pa + Pb = (Pa)' + (Pb)'
MV + Pb = - 3MV + (Pb)'
(Pb)' - Pb = MV + 3MV
ΔPb = 4MV
jadi, perubahan momentumnya 4MV.