The momentum is defined as:
[tex]p=mv[/tex]where m is the mass and v is the velocity of the object.
Plugging the values given and solving for v we have:
[tex]\begin{gathered} 6.7=4.5v \\ v=\frac{6.7}{4.5} \\ v=1.49 \end{gathered}[/tex]Therefore the rock was moving at 1.49 m/s (rounded to two decimals)
