HOMEWORK: A bear -y scary situation. A young girl is in the woods when she encou

Question

HOMEWORK: A bear -y scary situation. A young girl is in the woods when she encounters a bear. Upon encountering the bear she lets out a very loud scream at a pitch of 75.2 Hz. She will then run at a speed of 8.52 m/s (she is a very fast girl). The confused bear will run at a speed of 18.9 m/s. In each case you are going to find the frequency of sound the bear receives. A) The girl is running away from the bear and the bear is running away from the girl. B) The girl is running towards the bear and the bear is running away from the girl. C) The girl is running away from the hear and the bear is chasing the girl. D) The girl is running towards the bear and the bear is running towards the girl (sorry, no slow motion).

Explanation / Answer

A) both the girl and bear moving away from each other

frequency heard by the bear is f' = (V-Vo)*f/(V+Vs)

V is the speed o fthe sound V = 343 m/s

Vo is the speed of the bear = 18.9 m/s

Vs is the speed of the girl = 8.52 m/s

f is the frequency of the sound produced by girl = 75.2 Hz

then required frequency is f' = (343-18.9)*75.2/(343+8.52) = 69.33 Hz

B) here f' = (V-Vo)*f/(V-Vs) = (343-18.9)*75.2/(343-8.52) = 72.86 Hz

C) f'= (V+Vo)*f/(V+Vs) = (343+18.9)*75.2/(343+8.52) = 77 H.42 hz

D) f' = (V+Vo)*f/(V-Vs) = (343+18.9)*75.2/(343-8.52) = 81.36 Hz

Related Questions

Navigate

• Browse (All)
• Browse H
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.