A6 kg fish swimming 3 m/s swallows an absent minded 1 kg fish at rest. what is the speed of the large fish immediately after lunch? what would its speed be if the small fish were swimming towards it at 4 m/s?

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s

the rearrangement of particles in a physical change. hope this