physics
posted by Georgey on .
A water tank is filled to a depth of 10 m and the tank is 20 m above ground. The water
pressure at ground level in a hose 2 cm in diameter is closest to:
A) 3.9 × 105 N/m2
B) 2.0 × 104 N/m2
C) 9.2 N/m2
D) The crosssectional area of the tank is needed.

rho g h = 1000 (9.81)(30) = 2.94*10^5
add 1 atm = 1*10^5
and get total of 3.9 * 10^5 
Thank you boss!

Why do you need to add the 1 atm? And the 2 cm in this question does not matter?

Because the air we live in also has pressure
no pressure change in a horizontal hose with no flow through it.