Frequency change:

$\overline{){{\mathbf{f}}}_{\mathbf{o}\mathbf{b}\mathbf{s}}{\mathbf{=}}{\mathbf{f}}{\mathbf{\left(}}\frac{{\mathbf{v}}_{\mathbf{w}}}{{\mathbf{v}}_{\mathbf{w}}\mathbf{\pm}{\mathbf{v}}_{\mathbf{s}}}{\mathbf{\right)}}}$

Where f_{obs} is the frequency perceived by the observer, f is the frequency of the source, v_{w} is the velocity of the wave, and v_{s} is the velocity of the source.

Suppose an oncoming ambulance moving at 115 km/h emits a steady 785-Hz sound from its siren

What frequency, in Hz, is received by a person watching the oncoming ambulance? The speed of sound on this day is 345 m/s

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the The Doppler Effect concept. You can view video lessons to learn The Doppler Effect. Or if you need more The Doppler Effect practice, you can also practice The Doppler Effect practice problems.