Answer:
Therefore, the correct option is c: 0.
Explanation:
We can find the speed of the combined object by conservation of linear momentum:
[tex] p_{i} = p_{f} [/tex]
[tex] m_{1}v_{1_{i}} + m_{2}v_{2_{i}} = m_{1}v_{1_{f}} + m_{2}v_{2_{f}} [/tex]
Where:
"i" is for initial and "f" is for final
m₁: is the mass of the first object = m
m₂: is the mass of the second object = 3m
v₁: is the velocity of the first object
v₂: is the velocity of the second object
[tex] mv - 3m\frac{v}{3} = (m + 3m)v_{f} [/tex]
[tex] mv - mv = 4mv_{f} [/tex]
[tex] v_{f} = 0 [/tex]
Therefore, the correct option is c: 0.
I hope it helps you!
