Speed of sound/Dectecting insects

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Bats can detect insects roughly the size of one wavelength of the sound they emit, which is crucial for understanding their echolocation abilities. When a bat emits a chirp at 59 kHz and the speed of sound is 340 m/s, the smallest detectable insect size can be calculated using the appropriate formula. The user initially struggled to find the correct equation but realized the importance of focusing on the wavelength concept. After some calculations and unit checks, they arrived at a size of approximately 5.763 mm for the smallest insect detectable by the bat. This discussion highlights the simplicity of the problem once the right approach is recognized.
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I've looked throughout my book for the formula, and I've looked online to see if there were similar problems so I could figure out how to do this, but I can't find anything.

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A bat can detect small objects, such as insects, whose size is approx. equal to one wavelength of the sound the bat makes. If bats emit a chirp at a freq. of 59 kHz, and if the speed of sound in air is 340m/s, what is the smallest insect (mm) a bat can detect?

Maybe it's easier than I think. I'm definitely not a physics person. I'm not asking for the answer, just some help in find the right equation :)

Thanks for any help.
 
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Well. That's simple. I think the whole time I just wasn't reading "approximately equal to one wavelength.."

So, 340 m/s * 1,000 = 340,000 mm/s / 59 kHz = 5,762.

I've got to be doing something wrong/missing a step.
 
Check the units.
 
Duh. Yes. Thank you!

5.763 :)

I feel stupid. Now that seems like a REALLY simple problem.
 
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