Which object has the least momentum?
object a: m = 1 kg, v = 100 m/s
object b: m = 10 kg, v = 12 m/s
object c: m = 0.5 kg, v = 1000 m/s
object d: m = 100 kg, v = 2 m/s

Arigid tank is divided into two equal parts by a partition. one part of the tank contains 3 kg of compressed liquid water at 400 kpa and 60°c while the other part is evacuated. the partition is now removed, and the water expands to fill the entire tank. determine the entropy change of water during this process, if the final pressure in the tank is 40 kpa. use steam tables.

Aheavy boy and a lightweight girl are balanced on a massless seesaw. the boy moves backward, increasing his distance from the pivot point. what happens to the seesaw? it is impossible to predict without knowing additional information. the side the boy is sitting on will tilt downward. the side the girl is sitting on will tilt downward. nothing; the seesaw will remain balanced.

When a pendulum is held high and taut and then is released, the pendulum begins to swing. what’s the correct order of the energy transformations in this example? (pe stands for potential energy.)