Question

[img]https://upload.cc/i1/2020/04/13/StisGB.jpg[/img]

question is in picture,d8=4

Answer 1

(i) The frequency that the truck driver would hear as he moves toward the police car is

$$f=f_0\frac{u+v_t}{u-v_p}=1400\frac{343+15}{343-26}=1581\text{ Hz}.$$

(ii) The frequency that the truck driver would hear as he moves away from the police car is

$$f=f_0\frac{u-v_t}{u+v_p}=1400\frac{343-15}{343+26}=1244\text{ Hz}.$$