- 14 Continuing From The Previous Question A School Of Fish Swim Directly Beneath The Boat And Result In A Pulse Returni 1 (119.59 KiB) Viewed 77 times
14. Continuing from the previous question, a school of fish swim directly beneath the boat and result in a pulse returning to the boat in 0.150 s. How far above the sea floor are the fish swimming? (a) 5480 m (b) 742 m (c) 115 m (d) 38.3 m 15. A first-year university student eats an apple rather loudly during class. What is the intensity of the sound 2 metres away if the biting sound is output at 20 W? (a) 0.1 W m-2 (b) 0.2 W m-2 (c) 0.3 W m-2 (d) 0.4 W m-2 16. The following three questions relate to the following information: The fundamental frequency of a string 2.40 m long, fixed at both ends, is 22.5 Hz. What is the wavelength of the wave in the string at its fundamental frequency? (a) 0.11 m (b) 1.20 m (c) 2.40 m (d) 4.80 m 17. The frequencies of the first two overtones that may be formed by this length of string are (a) 45 Hz and 67.5 Hz (b) 45 Hz and 90 Hz (c) 22.5 Hz and 45 Hz (d) 67.5 Hz and 90 Hz 18. The speed of the wave in this string is compare with the velocity of sound in air : 346 ms-), (a) 54 m s-1 (b) 108 ms -1 (c) 216 ms-1 (d) 346 ms -1 19. What is the period of a simple pendulum 67 cm long on Mars? The mass and radius of Mars are 6.39 x 1023 kg and 3.39 x 106 m, respectively. (a) 28.4 s (b) 14.8 (C) 2.67 s (d) 0.067 s