Question

Water is flowing at a steady rate through a homogeneous and saturated horizontal soil strip of 10 m length. The strip is being subjected to a constant water head of 5 m at the beginning and 1 m at the end. If the governing equation of flow in the soil is $d^{2}H/d{x}^2=0$ (x = distance along the soil strip) value of H (in m) at the middle of the strip is

• A. 3

Answer 1

The correct option is A 3


$\frac{d^{2}H}{d{x}^2}=0$

$\frac{dH}{dx}=K$

H = Kx + C

at x = 0, H = 5 $\Rightarrow$ c = 5

at x = 10, H = 1

$\Rightarrow 1=K\times 10+5$

K = -0.4

H = -0.4x +5

Value of H at

x = 5 m = -0.4 $\times$ 5 + 5 = 3 m