Physics (AS & A Level) · May / June 2019 · Paper 12 · Question 23

The diagram illustrates the position of particles in a progressive sound wave at one instant in time. The speed of the wave is v. P and Q are two points in the wave a distance L apart. What is an expression for the frequency of the wave?

1. A\frac{v}{2L}
2. B\frac{v}{L}
3. C\frac{2v}{L}
4. D\frac{L}{v}

As printed in the paper