Question

Horseshoe bats (genus Rhinolophus) emit sounds from their nostrils, then listen to the frequency of the sound reflected from their prey to determine the prey's speed. (The "horseshoe" that gives the bat its name is a depression around the nostrils that acts like a focusing mirror, so that the bat emits sound in a narrow beam like a flashlight.) A Rhinolophus flying at speed vbat emits sound of frequency fbat; the sound it hears reflected from an insect flying toward it has a higher frequency frefl.

Part A

If the bat emits a sound at a frequency of 80.1 kHz and hears it reflected at a frequency of 83.5 kHz while traveling at a speed of 4.4 m/s , calculate the speed of the insect.

Answer 1

The speed of in seet is Unsect r frelt Cove-o bat) - flat roet Ubat) 7 freti cu-Ubat) + f bat ( + Ubat) 4029 29 lect speed of sound = 343m/s. Vinsecet - 343 / 83.5X10343-4.4)- 80.1X10(343+44) 183.5x183 (343-44)-80.13183 (3434409) Vinsect = 2.13 m/s