A car horn has wavelength 0.5 m. Sound speed is 340 m s⁻¹. Find its frequency.

Solution & explanation

1. Given: v = 340 m s⁻¹; λ = 0.5 m.

2. Find: f in Hz

3. Start with v = fλ.

   $$v=f\times \lambda$$

4. Divide both sides by wavelength.

   $$f=\frac{v}{\lambda }$$

5. Substitute speed and wavelength.

   $$f=\frac{340}{0.5}$$

6. Perform the division.

   $$f=680.0$$

7. State the result with units: f = 680 Hz

f = 680 Hz