Ten questions. The result tells you which lessons you may skip.
Two sounds of slightly different frequencies are heard together at one point. What are beats?
Tuning forks of \(256\,\text{Hz}\) and \(259\,\text{Hz}\) are sounded together. The number of beats per second is
Tones of \(440\,\text{Hz}\) and \(444\,\text{Hz}\) of equal amplitude sound together. The pitch heard inside the beats is
Fork B gives \(4\) beats per second with a \(256\,\text{Hz}\) fork. After a little wax is put on B, the beats fall to \(2\) per second. The frequency of B before waxing was
A source at rest emits \(510\,\text{Hz}\). An observer moves towards it at \(20\,\text{m/s}\). Take \(c = 340\,\text{m/s}\). The observer hears
A \(660\,\text{Hz}\) source moves at \(40\,\text{m/s}\) towards an observer at rest. Take \(c = 340\,\text{m/s}\). The observer hears
In \(f' = f(c \pm v_O)/(c \mp v_S)\), a source moving away from the observer takes
A car with its horn sounding passes a listener standing beside the road. At the instant the car is closest to the listener, the frequency heard is
An observer walks quickly towards a source at rest. The wavelength of the sound in the air between them
A source moves through still air slower than sound. Its wavefronts are