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3 years ago

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Bats can detect small objects such as insects that are of a size on the order of a wavelength. if bats emit a chirp at a frequen

cy of 69.3 khz and the speed of sound waves in air is 330 m/s, what is the smallest size insect they can detect? give your answer in mm (millimeters)

1 answer:

crimeas [40]3 years ago

6 0

The smallest size of the insect that the bats can detect corresponds to the wavelength of the chirp they emit.

Their chirp has a frequency of
$f=69.3 kHz=69.3 \cdot 10^3 Hz$
and the speed of the chirp is equal to the speed of sound in air:
$v=330 m/s$
Therefore the wavelength of the chirp is
$\lambda= \frac{v}{f}= \frac{330 m/s}{69.3 \cdot 10^3 Hz}=4.76 \cdot 10^{-3} m$
which corresponds to a size of 4.76 mm.

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Answer:

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Explanation:

As we know that resistance of one copper wire is given as

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now we have

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now we know that such 17 resistors are connected in parallel so we have

$R = \frac{r}{17}$

$R = \rho \frac{4L}{17 \pi d^2}$

Now if a single copper wire has same resistance then its diameter is D and it is given as

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$\rho \frac{4L}{\pi D^2} = \rho \frac{4L}{17 \pi d^2}$

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max2010maxim [7]

Answer:

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2 years ago

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3 years ago

A 180 lb crate is on the ground, and a strong rope is attached. You need to move it across the basement floor, which has a coeff

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Answer:

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3 years ago