Chapter 11: Questions with Calculations

1. If three freight cars pass an observer every second and each freight car is 12 meters long, what is the speed of the freight train?

2. If three waves pass an observer every second and each wave has a wavelength of 12 cm, what is the speed of the wave?

3. At room temperature the speed of sound is about 345 m/s. What is the wavelength of a sound that has a frequency of 345 Hz?

4. At room temperature the speed of sound is about 345 m/s. What is the wavelength of a middle C that has a frequency of 262 Hz?

5. When a violin string is bowed, standing waves may be caused or excited. If the part of the string that can vibrate is 0.60 meters long, what are possible wavelengths for those standing waves?

6. When a guitar string is plucked, standing waves may be caused or excited. If the part of the string that can vibrate is 0.80 meters long, what are possible wavelengths for those standing waves?

7. Standing waves, with a single loop, are present on a rope when one end is vibrated at 120 Hz? What frequency is necessary to excite standing waves with two loops on the rope? What frequency is necessary to excite standing waves with three loops on the rope?

8. Standing waves, with two loops, are present on a rope when one end is vibrated at 150 Hz? What frequency is necessary to excite standing waves with a single loop on the rope? What frequency is necessary to excite standing waves with three loops on the rope?