Two objects are moving in the xy-plane. Object A has a mass of 3.2 kg and has a velocity of Va= (2.3 m/s)i + (4.2m/s)j and object B has a mass of 2.9 kg and has a velocity of Vb= (-1.8m/s)i + (2.7m/s)j.

Question

Two objects are moving in the xy-plane. Object A has a mass of 3.2 kg and has a velocity of Va= (2.3 m/s)i + (4.2m/s)j and object B has a mass of 2.9 kg and has a velocity of Vb= (-1.8m/s)i + (2.7m/s)j.
What is the total momentum of the system?

(should I use dot product here?)

Damon · Answer

sum of vectors, not product Pa =3.2[ 2.3 i + 4.2 j] = 7.36 i +13.44 j Pb =2.9[ -1.8 i +2.7 j] =-5.22 i +7.83 j P = (7.36-5.22) i +(13.44+7.83) j