tolong bantu jawab besok dikumpul...tolong pake cara kak supaya tau caranya

p = momentum
F = Δp : Δt
2 = 80 : Δt
Δt = 40 s

p (momentum) = m x v
p = 2 x 12
p = 24 kg m/s

tumbukan tidak lenting
m1v1 + m2v2 = ( m1 + m2) v'
2 x 10 + 3 x 0 = ( 2 + 3 )v'
20 = (5)v'
v'= 4 m/s

ma = mb = m
mava + mbvb = mava' + mbvb'
mva + mvb = ( m + m) v'
m = 2 m (v')
0,5 m/s = v'
ke kiri.