Answer:
B.) by interfering with sound waves
Explanation:
As we know that the interference of sound waves is of two types
1). constructive interference
2). destructive interference
now we know that constructive interference means the resultant intensity will be more than the intensity of interfering waves as here two waves are in same phase.
In destructive interference the resultant of two waves is given by the minimum resultant of the intensity as here the phase of two waves are opposite to each other.
So we will say that
here in case of noise cancelling headphones we know that the phase of noise is always made in opposite phase with the sound which is used to cancelled the noise.
This will reduce the noise and we will get a clear sound
Answer:
The height of the tree is three (3) deep
Explanation:
It's 3 deep
Under 129, comes 125 and 685;
Under 125, comes 52 : Under 685, comes 511;
Under 52, comes 46 : Under 511, is 601.
This is illustrated below.
129
∧
125,685
|,|
52,511
|,|
46,601
Explanation:
It is given that,
Wavelength of red laser light, 
The second order fringe is formed at an angle of, 
For diffraction grating,
, n = 2
The wavelength λ of light that creates a first-order fringe at 22 is given by :
Hence, this is the required solution.
That would be answer B
hope this helped you
Answer:
strong winds that blow for a long time over a great distance
weak winds that blow for short periods of time with a short fetch
Explanation:
When the winds are weak and blow for short periods, we experience the smallest ocean waves but when there are strong winds over a longer duration, the largest ocean waves are seen. Therefore, the conditions to produce the smallest and largest ocean waves are strong winds that blow for a long time over a great distance and weak winds that blow for short periods of time with a short fetch.
