Answer:
<em>1.06 atm</em>
Explanation:
On the open end of the tube, the pressure will be the sum of atmospheric pressure and the pressure due to the height of water
The pressure due to a height of water = ρgh
where ρ is the density of water = 1000 kg/m^3
g is the acceleration due to gravity = 9.81 m/s^2
h is the height of the water column
The height of water column on the open end = 100 cm = 1 m
pressure on this end = ρgh = 1000 x 9.81 x 1 = 9810 Pa
Atmospheric pressure = 101325 Pa
The total pressure on the open end = 101325 Pa + 9810 Pa = <em>111135 Pa</em>
The pressure due to the water column on the closed end = ρgh
The height of the water in the closed end = 40 cm = 0.4 m
The pressure due to this column of water = 1000 x 9.81 x 0.4 = <em>3924 Pa</em>
The resultant pressure on the water on the top of the closed end of the tube = 111135 Pa - 3924 Pa =<em> 107211 Pa</em>
In atm unit, this pressure = 107211/101325 = <em>1.06 atm</em>