Iona Prep Physics Problems from the textbook

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# 15 A sound wave produced by a clock chime is heard 515 m away 1.5 s later. (a)What is the speed of sound in the air there? (b) The sound wave has a frequency of 436 Hz. What is the period of the wave? (c) What is the wave's wavelength?

#16 A hiker shouts toward a vertical cliff 465 m away. The echo is heard 2.75 s later. (a) What is the speed of sound in air there? (b) The wavelength of the sound is 0.75 m. What is the frequency of the wave? (c) What is its period?

#17 If you wanted to increase the wavelength of waves in a rope should you shake it at a higher or lower frequency?

#18 What is the speed of a periodic wave disturbance that has a frequency of 3.5 Hz and a wavelength of 0.7 m?

#19 The speed of a transverse wave in a string is 15 m/s. If a source produces a disturbance that has a frequency of 6.0 Hz, what is its wavelength?

#20 Five pulses are generated every 0.1 s in a tank of water. What is the speed of propagation of the wave if the wavelength of the surface wave is 1.20 cm?

#21 A periodic longitudinal wave that has a frequency of 20.0 Hz travels along a coil spring. If the distance between successive compressions is 0.60 m, what is the speed of the wave?

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#75 The Sears Tower in Chicago sways back and forth in the wind with a frequency of about 0.12 Hz. What is the period of vibration?

#76 An ocean wave has a length of 12.0 m. A wave passes a fixed location every 3.0 s. What is the speed of the wave?

#90 AM radio signals are broadcast at frequencies between 550 kHz (kilohertz) and 1600 kHz and travel 3.0 x10^8 m/s. (a) What is the range of wavelengths for those signals? (b) FM frerquencies range between 88 MHz (megahertz) and 108 MHz and travel at the same speed. What is the range of FM wavelengths?

#94 You are about to bungee jump using a cord that is 10.0 m long. If you are able to reach to a height of 2.3 m and have a mass of 68 kg, and the cord has a spring constant of 55 N/m, how high should the platform be if you want to be able to just touch the floor when at the bottom of the jump? (There might be motivation for getting this answer correct!)

15. (a) 343 m/s (b) 2.29x10^-3 s (c) 0.787 m
16. (a) 338 m/s (b)451 Hz (c) 2.22x10^-3 s
17. lower
18. 2.45 m/s
19. 2.50 m
20. 0.600 m/s
21. 12.0 m/s

75. 8.3 s
76. 4.0 m/s
90. 190 m – 550 m
94. 24m