Answer:
The speed of the police car is 33.98 m/s
Explanation:
Given;
first speed, v₁ = 35 m/s
first frequency, f₁ = 1370 Hz
second frequency, f₂ = 1330 Hz
second speed, v₂ = ?
Speed of sound is directly proportional to its frequency;
v = fλ
assuming the λ is constant, then,
[tex]\lambda = \frac{V}{F}\\\\\frac{V_1}{F_1} = \frac{V_2}{F_2}\\\\V_2 = \frac{V_1F_2}{F_1}\\\\V_2 = \frac{35*1330}{1370}\\\\V_2 = 33.98 \ m/s[/tex]
Therefore, the speed of the police car is 33.98 m/s