contestada

A car horn creates a 595 hz tone
at rest. two cars pass on the
street, each going 20.0 m/s; the
first car honks. what frequency
does the other car hear after they
pass each other?
(speed of sound = 343 m/s)
(unit = hz)

Respuesta :

Snor1ax

Answer: 669 Hz

Explanation:

The frequency, f', at which the other car hears the honk is what we have to find. We do this by using the equation for the Doppler effect,

[tex]f' = \left( \frac{v+v_o}{v-v_s} \right)f[/tex]

Where:

  • [tex]f =\rm 595\ Hz[/tex] is the frequency of the horn
  • [tex]v =\rm 343\ m/s[/tex] is the speed of sound
  • [tex]v_s =\rm 20.0\ m/s[/tex] is the speed of the first car
  • [tex]v_o =\rm 20.0\ m/s[/tex]  is the speed of the other car

We proceed with the solution,

[tex]\displaystyle f' &= \left( \frac{v+v_o}{v-v_s} \right)f\\[0.3cm] &=\rm \left( \frac{( 343\ m/s)+(20.0\ m/s)}{( 343\ m/s)-(20.0\ m/s)} \right)( 595\ Hz)\\[0.3cm] &\approx\boxed{\rm 669\ Hz}[/tex]

Otras preguntas