What is the momentum of an object with mass 8 kg and velocity 5 m/s

What if? if the temperature near the cliff suddenly falls to 0°c, reducing the speed of sound to 331 m/s, what would the initial speed of the rock have to be (in m/s) for the soccer player to hear the sound of the splash 2.90 s after kicking the rock?

How much work would a child do while puling a 12-kg wagon a distance of 3m with a 22 n force directed 30 degrees with respect to the horizontal? (a) 82j (b) 52j (c) 109j (d) 95j

Where is the potential energy throughout the loading, cocking, and releasing of the trebuchet?