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ASHA 777 [7]
3 years ago
12

If you suspect your culture of bacteria has 25 x 107 cells per mL, what would you want the final dilution to be in order to end

up with 100 cfu on a plate?
Physics
1 answer:
Delicious77 [7]3 years ago
4 0

Answer:

dilution = 2.5*10^6

Explanation:

Given:

- Number of colonies N = 100 cfu

- The Volume of cells = 25*10^7 cells / ml

Find:

the final dilution

Solution:

- The expression relating the the colonies forming unit with cells//volume is given as:

                                       Bacteria/ml = cfu*dilution

                                       dilution = Volumetric cells/ cfu

                                       dilution = 25*10^7 / 100

                                       dilution = 2.5*10^6

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spin [16.1K]

Answer:

L=0.654 m

Explanation:

<u>Concepts and Principles  </u>

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<u>Standing Wave Patterns in Pipes:  </u>

A pipe open at both ends can have standing wave patterns with resonant frequencies:  

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<u>Given Data </u>

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T (temperature of the air) = 20°C  

The flute is open at both ends.  

<u>Required Data </u>

We are asked to determine the length of the tube.  

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The speed of sound in air at temperature T = 20°C is found from Equation (1):

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7 0
3 years ago
A particularly beautiful note reaching your ear from a rare stradivarius violin has a wavelength of 39.1 cm. the room is slightl
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The wavelength of the note is \lambda = 39.1 cm = 0.391 m. Since the speed of the wave is the speed of sound, c=344 m/s, the frequency of the note is
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Then, we know that the frequency of a vibrating string is related to the tension T of the string and its length L by
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Using the value of the tension, T=160 N, and the frequency we just found, we can calculate the length of the string, L:
L= \frac{1}{2f}  \sqrt{ \frac{T}{\mu} } =0.31 m
8 0
3 years ago
Halp me please i will give brainly
Delicious77 [7]

Answer: It should be the 3rd option down!

Explanation:

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