A car stop at 50 m nearest to a junction road-train. A train is moving with a constant velocity 30 ms-1 towards the junction. If the train emits siren at frequency 1000hz. Calculate the frequency heard by car driver when train is at 80m from the junction.

Question

A car stop at 50 m nearest to a junction road-train.  A train is moving with a constant velocity 30 ms-1 towards the junction.  If the train emits siren at  frequency 1000hz. Calculate the frequency heard by car driver when train is at 80m from the junction.

dream95 · Answer

use velocity of sound =343 ms-1

anonymous · Answer

$$f _{observed} =\frac{ v }{ v-v _{s}}* f _{source} $$

you can use this.
Where; 
 v is sound velocity 
vs is source velocity