A physics class is experimenting with sound waves in the hallway of their school. Student A is holding his physics textbook out in front of him at one end of the hallway. At the other end of the hallway, 100 m away, two students (student B and student C) are listening for the sound of the textbook hitting the floor, ready to raise a hand as soon as they hear the sound. Student B is standing up, while student C is laying down with her ear pressed against the floor. When student A drops the textbook, student C is the first to raise her hand. Explain why student C hears the sound before student B. (DOK 2 A. Student C has her ear pressed against the solid floor, and sound travels faster in solids than in gases (like air) O B. Student C was laying on the ground, and sound travels faster through lower air near the floor OC. The speed of sound is constant, so student C just raised her hand faster O D. Student C has her ear pressed against the cold floor, sound travels faster at cold temperatures

A warehouse building has two open doors along one wall as shown in the figure. The walls of the warehouse are lined with a sound-absorbing material. Two people stand at distance L = 103m from the wall with the open doors as shown. A train runs past the warehouse, blowing its horn to produce a loud sound with a frequency of 581 Hz. To person A, the sound of the train is loud and clear. To person B, the sound is barely audible. Assuming that person B is at the position of the first minimum in the sound interference pattern, determine the center-to-center distance d between the doors. Assume room temperature air. Image size: s M L Max open door у320 m A open door (figure not to scale)

A teacher shouting at the top of his lungs emits about 1.0 W of energy as sound waves. Student A is standing 2.0 m away. Student B is standing 20 m away. Compare the sound intensity at these two locations. O 11 = 1012 O 11 =12 O none of the given O 10011 = 12 O 101₁1 =12 11 = 10012

In each of the four scenarios shown in the images, a large bat lets out a short burst of ultrasonic sound, which a smaller bat hears a moment later. If the large bat flies at 2.320 m/s and the small bat flies at 13.80 m/s, order the frequencies that the smaller bat detects in the four scenarios from highest to lowest. Assume that the speed of sound is 343.0 m/s. Highest frequency A D B. A B C Lowest frequency Answer Bank In Scenario C, part of the large bat's signal reflects off the small bat and returns to the large bat, warning it of the smaller bat's presence. If the initial signal has a frequency of 66.70 kHz, what return frequency fr will the large bat detect? Calculate the final frequency to four significant figures. fr Incorrect kHz Ꭰ