How things work college course/Waves (Physics Classroom)

This quiz was inspired by: http://www.physicsclassroom.com/class/waves/Lesson-1/Waves-and-Wavelike-Motion
 * /Testbank/ contains printable pdf files, randomized for use in a classroom.

{These two pulses will collide and produce} + positive interference - negative interference - positive diffraction - negative diffraction {These two pulses will collide and produce} - positive interference + negative interference - positive diffraction - negative diffraction {These two pulses will collide and produce} + positive interference - negative interference - positive diffraction - negative diffraction { Two signals (dashed) add to a solid} + octave - fifth - dissonance { Two signals (dashed) add to a solid} - octave - fifth + dissonance { Two signals (dashed) add to a solid} - octave + fifth - dissonance {Why don't we hear beats when two different notes on a piano are played at the same time?} + The beats happen so many times per second you can't hear them. - The note is over by the time the first beat is heard - Reverberation usually stifles the beats - Echo usually stifles the beats {A tuning fork with a frequency of 440 Hz is played simultaneously with a tuning fork of 442 Hz. How many beats are heard in 10 seconds?} + 20 - 30 - 40 - 50 - 60 {If you start moving towards a source of sound, the pitch becomes} + higher - lower - unchanged {If a source of sound is moving towards you, the pitch becomes} + higher - lower - unchanged {Why do rough walls give a concert hall a “fuller” sound, compared to smooth walls?} - Rough walls make for a louder sound. + The difference in path lengths creates more reverberation. - The difference in path lengths creates more echo. {People don't usually perceive an echo when} + it arrives less than a tenth of a second after the original sound - it arrives at exactly the same pitch - it arrives at a higher pitch - it arrives at a lower pitch - it takes more than a tenth of a second after the original sound to arrive {A dense rope is connected to a rope with less density (i.e. fewer kilograms per meter). If the rope is stretched and a wave is sent along high density rope,} - the low density rope supports a wave with a higher frequency - the low density rope supports a wave with a lower frequency + the low density rope supports a wave with a higher speed - the low density rope supports a wave with a lower speed {What happens to the wavelength on a wave on a stretched string if the wave passes from lightweight (low density) region of the rope to a heavy (high density) rope?} + the wavelength gets longer - the wavelength stays the same - the wavelength gets shorter {When a wave is reflected off a stationary barrier, the reflected wave} + has lower amplitude than the incident wave - has higher frequency than the incident wave - both of these are true {Comparing a typical church to a professional baseball stadium, the church is likely to have} + reverberation instead of echo - echo instead of reverberation - both reverberation and echo - neither reverberation nor echo