When liquid state is being converted to solid state, atoms come closer to each other and their speed of movement also decreases. Instead of moving about in the substance, they are only able to vibrate about their positions in solid. Hence, this change leads to loss of energy. Similarly, atoms loose energy when state changes from gas to liquid.
Answer:
The answer to the question is
The height of the mercury fluid column remain the same.
Explanation:
The pressure, P in a column of fluid of height, h is given by
P = (Density p)×(height of fluid column h)×(gravity g)
Therefore, when the diameter is doubled we have
Density of the mercury in the tube with twice the diameter = (Mass of mercury)/(volume of mercury) where the volume of mercury = h×pi×(Diameter×2)^2/4 = h×pi×Diameter^2. Therefore the volume increases by a factor of 4 and therefore the mass increases by a factor of 4 which means that the density remains the same hence
P = p×h1×g = p×h2×g Therefore h1 = h2
The height of the fluid column remain the same