Answer:
As the sound approaches, it gets louder (simply because you're closer to the source), and has a higher pitch. Then, as it passes, the sound suddenly dips down, and as it drives away you hear a lower pitch, plus a decreasing volume as the engine gets farther and farther away.
Explanation:
Water expands when it freezes (that's why you should never put closed, fully filled water bottles in the freezer !)
Answer:
he kinetic energy increases on the descent, being maximum at the lowest point of the trajectory.
Explanation:
In these semicircular sections the skaters slide from one side to the other, in the downward path their kinetic energy increases and their potential energy decreases; When it leaves the ramp and is in the air, the kinetic energy decreases rapidly, up to the point of maximum height where the kinetic energy is zero.
Consequently, the kinetic energy increases on the descent, being maximum at the lowest point of the trajectory.