1.8461 km/hr Well i need more characters so i might as well type a beautiful sentence for you to read and waste your time on.
Education that result in understanding and the spread knowledge physics
Answer:
The thickness is 
Explanation:
From the question we are told that
The wavelength is 
The first order of the dark fringe is 
The second order of dark fringe considered is 
Generally the condition for destructive interference is mathematically represented as

Here y is the path difference between the central maxima(i.e the origin) and any dark fringe
So the path difference between the 16th dark fringe and the 6th dark fringe is mathematically represented as

=> 
=> 
=> 
Answer:
different value to l if n=5 are 0,1,2,3,4
Echoes occur when a reflected soundwave reaches the ear more than 0.1 seconds after the original sound wave was heard. ... There will be an echoinstead of a reverberation. Reflection of sound waves off of surfaces is also affected by the shape of the surface.
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