Respuesta :
Answer:
A) The driver should drive away from the pet owner to use the Doppler effect
Explanation:
The whistle claims to be making a frequency higher than the audible frequency to humans
We need to decrease its frequency to make it audible.
Doppler effect explains the influence of motion of the source on the observed frequency.
If the source is approaching the observed frequency will be higher than the real frequency.
For an approaching source
[tex]f_{observed}=f_{source}(\frac{v}{v+v_{source}} )[/tex]
If the source is receding the observed frequency will be lower than the real frequency
For a receding source
[tex]f_{observed}=f_{source}(\frac{v}{v-v_{source}} )[/tex]
From the above facts we understand that the helper should ride away from the pet owner to decrease the frequency and make the whistle audible.