Answer:
•→ The motion of a particle or body in S.H.M acts towards a fixed point.
•→ Acceleration of the body under S.H.M is proportional to its displacement.
•→ This motion is periodic.
•→ Mechanical energy is conserved in S.H.M
Explanation:
S.H.M is Simple Harmonic Motion

Solution :
Given data is :
Density of the milk in the tank, 
Length of the tank, x = 9 m
Height of the tank, z = 3 m
Acceleration of the tank, 
Therefore, the pressure difference between the two points is given by :

Since the tank is completely filled with milk, the vertical acceleration is 

Therefore substituting, we get




Therefore the maximum pressure difference in the tank is Δp = 47.87 kPa and is located at the bottom of the tank.
<u>Answer</u>:
When light passes through an object unchanged, scientists call that process Transmission.
<u>Explanation</u>:
Transmission is the process where all the light that is passed through the material moves via the material without being absorbed. The Transmission depends on the affected radiation.The Transmittance of the medium is defined as the ratio between transmitted radiant power and incident radiant power. The light that is passed through the medium and not reflected will be either scattered or reflected. The light can be transmitted only through transparent or translucent material. Opaque object does not allows transmission of light.