Question

A 3,000 kg truck is traveling 28 m/s through a rainstorm. At the end of its journey, it has collected 500 kg of water and is now moving 24 m/s. Was momentum conserved?

Answer 1

The mass of the truck is M = 3000 kg and the initial speed of the truck is u = 28 m/s.

After traveling through the rainstorm, the mass of the water is m = 500 kg is collected in the truck, the final mass will be m+M = 3500 kg and the final speed of the truck is v = 24 m/s.

The momentum is conserved if initial momentum = final momentum

On substituting the values,

`\begin{gathered} Initial\text{ momentum =Mu} \\ =3000*28 \\ =84000\text{ kg m/s} \\ F\text{inal momentum = (m+M)v} \\ =3500*24 \\ =84000\text{ kg m/s} \end{gathered}`

Thus, the momentum is conserved.