Answer:
minimum frequency = 170 Hz
Explanation:
given data
One path long = 20 m
second path long = 21 m
speed of sound = 340 m/s
solution
we get here destructive phase that is path difference of minimum
here λ is the wavelength of the wave
so path difference will be
21 - 20 =
λ = 2 m
and
velocity that is express as
velocity = frequency × wavelength .............1
frequency =
minimum frequency = 170 Hz
Cumulus and cumulonimbus<span />
Explanation:
Given that,
Rate of cooling of air
Initial temperature= 80°C
Final temperature = 5°C
We need to calculate
Using newton's law of cooling


Where, 
Here,
= 25°C (surrounding temperature)
dt = 1 minute

Put the value into the formula



Hence, This is the required answer.
We will make the comparison between each of the sizes against the known wavelengths.
In the case of the <em>hydrogen atom</em>, we know that this is equivalent to
m on average, which corresponds to the wavelength corresponding to X-rays.
In the case of the <em>Virus</em> we know that it is oscillating in a size of 30nm to 200 nm, so the size of the virus is equivalent to the range of the wavelength of an ultraviolet ray.
In the case of <em>height</em>, it fluctuates in a person around
to
m, which falls to the wavelength of a radio wave.