At Colorado State University we are familiar with trains and their horns. You stand a safe distance next to the track and a train, which is 20 m away, travels towards you. You detect the train's horn at an intensity level of 120 dB and a frequency of 462 Hz. Multiple Choice Questions 7) You know that the train air horn is actually emitting sound at 440 Hz. How fast is the train moving towards you? a) 8 m/s b) 10 m/s c) 12 m/s d) 14 m/s e) 16 m/s f) 18 m/s 8) What distance would you need to be from the train for the sound intensity level to be 80 dB? a) 10 m b) 30 m Short Answer Question c) 100 m d) 700 m e) 1,300 m f) 2,000 m A locomotive (150,000 kg) has initial speed given by your answer to Question 7. It collides with a tanker car (50,000 kg) that is initially at rest; the two couple and move off together in a completely inelastic collision. . What is the speed (in m/s) of the two train cars immediately after the collision? . What is the energy dissipated (in J) during the collision? ⚫ If the collision lasts 2s, what is the average force (in N) of the collision?