Answer: f = 927.55Hz
Explanation: Since the the tube is open-closed, the length of air and the wavelength of sound passing through the tube is given below
L = λ/4 where λ = wavelength.
speed of sound in air = v = 343m/s.
fundamental frequency of open closed tube = 315Hz
λ = 4L.
v = fλ
343 = 315 * 4L
343 = 1260 * L
L = 343/ 1260
L = 0.27m
In the same tube of length L = 0.27m but different medium ( helium), the speed of sound is 1010m/s.
The length of tube and wavelength are related by the formulae below
L = λ/4, λ=4L
λ = 4 * 0.27
λ = 1.087m.
v = fλ
1010 = f * 1.087
f = 1010/1.807
f = 927.55Hz
Answer:
The surface tension is 0.0318 N/m and is sufficiently less than the surface tension of the water.
Solution:
As per the question:
Radius of an alveolus, R = 
Gauge Pressure inside, 
Blood Pressure outside, 
Now,
Change in pressure, 
Since the alveolus is considered to be a spherical shell
The surface tension can be calculated as:
And we know that the surface tension of water is 72.8 mN/m
Thus the surface tension of the alveolus is much lesser as compared to the surface tension of water.
Answer:
NASA's Chandra X-ray Observatory and other telescopes such as the Hubble telescope.
Explanation:
Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies.
The above observations have provided the strongest evidence yet that most of the matter in the universe is dark.
Answer:
The 
electrons are moving through the superconductor per second.
Explanation:
Given :
Current 
A
Charge of electron 
C
Time 
sec
From the formula of current,
Current is the number of charges flowing per unit time.
Where 
number of charges means in our case number of electrons
Therefore, electrons are moving through the superconductor per second.
