Answer:
The phase difference is
Explanation:
From the question we are told that
The distance between the loudspeakers is 
The distance of the listener from the wall 
The frequency of the loudspeakers is 
The velocity of sound is 
The path difference of the sound wave that is getting to the listener is mathematically represented as

Substituting values


The phase difference is mathematically represented as
= 
Where
is the wavelength which is mathematically represented as

substituting value


Substituting value into the equation for phase difference
= 
Answer:
No, it is not necessary for them to have same mass.
Explanation:
Let both bodies have a density d1 and d2 respectively.
Since their volumes are equal V1 = V2
we know that, https://tex.z-dn.net/?f=%5Cfrac%7Bmass%7D%7Bvolume%7D
Hence, d1 = and d2 =
Taking the ratio of densities,we get
This implies that unless the bodies have same densities, the mass of the two bodies will not be same.
A wave that is oscillation of matter.. such as a water ripples
Answer:

between the plates.
Explanation:
The equation for change of voltage between two points separated a distance d inside parallel conducting plates (<em>which have between them constant electric field</em>) is:

So to calculate our electric field strength we use the fact that the potential 8.8 cm from the zero volt plate is 475 V:

And we use the fact that the plates are 9.2cm apart to calculate the voltage between them:
