Question

Superman attempts to drink water through a very long vertical straw. With his great strength, he achieves maximum possible suction. The walls of the tubular straw don't collapse.
(a) Find the maximum height through which he can lift the water.
m
(b) Still thirsty, the Man of Steel repeats his attempt on the Moon, which has no atmosphere. Find the difference between the water levels inside and outside the straw.
m

Answer 1

Answer:

10.32874 m

Explanation:

$P_a$ = Atmospheric pressure = 101325 Pa

g = Acceleration due to gravity = 9.81 m/s²

h = Height of water

$\rho$ = Density of water = 1000 kg/m³

If the walls of the tube do not collapse that means that maximum pressure inside will be the atmospheric pressure

Atmospheric pressure is given by

$P_a=\rho gh\\\Rightarrow h=\dfrac{P_a}{\rho g}\\\Rightarrow h=\dfrac{101325}{1000\times 9.81}\\\Rightarrow h=10.32874\ m$

The maximum height to which Superman can lift the water is 10.32874 m

On the Moon there is no atmosphere so no atmospheric pressure which means when the straw is placed in water water will not rise in the tube.