Waves and Sounds - speed of a bat

  • Thread starter Thread starter FrenchAtticus
  • Start date Start date
  • Tags Tags
    Speed Waves
AI Thread Summary
A bat chasing an insect emits a 52 kHz chirp and receives an echo at 52.75 kHz, prompting a calculation of its speed gain. The speed of sound in air is given as 342 m/s. The equation used for the Doppler effect was set up correctly, but the calculation for the observer's velocity (vo) yielded a value that didn't align with expectations. The user seeks assistance in resolving the discrepancy in their calculations to determine the bat's speed gain accurately. Clarification on the Doppler effect application is needed for a correct solution.
FrenchAtticus
Messages
10
Reaction score
0

Homework Statement



A bat moving at 4.5 m/s is chasing a flying insect insect. The bat emits a 52 kHz chirp and receives back an echo at 52.75 kHz. At what speed is the bat gaining on its prey? Take the speed of sound in air to be 342 m/s.


Homework Equations




f1 = f ((velocity +/- velocity observer)/(velocity +/- velocity source))

The Attempt at a Solution



To start off, I converted 52 kHz to 52,000 Hz and 52.75 kHz

Then my equation looked like:

52750 = 52000 ((342 - vo)/(342-4.5)

I found vo to be .367788 and subtracted that from 4.5 to find the speed gained, but that doesn't seem to work. Can anyone help?
 
Physics news on Phys.org
Can anybody help me out?
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top