An 800 kg roller coaster car travels along the track. The magnitude of the car's velocity at point Y is 30 m/s.
What is the car's kinetic energy at Y?

Afisherman notices that his boat is moving up and down periodically, owing to waves on the surface of the water. it takes a time of 2.70 s for the boat to travel from its highest point to its lowest, a total distance of 0.700 m. the fisherman sees that the wave crests are spaced a horizontal distance of 6.50 m apart. a. how fast are the waves traveling? b. what is the amplitude a of each wave?

The amount of potential energy possessed by an elevated object is equal to

Whithin which type of system is neither the total mass nor the total energy conserved ? a. open b. connected c. isolated d. closed