Question

The deflection of flow lines at interface of dissimilar soils is given by ______

(a) \(\frac{k_1}{k_2} =cosθ\)

(b) \(\frac{k_1}{k_2} =sinθ \)

(c) \(\frac{k_1}{k_2} =\frac{tanθ_1}{tanθ_2} \)

(d) \(\frac{k_1}{k_2} =cotθ\)

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Answer 1

The correct choice is (c) \(\frac{k_1}{k_2} =\frac{tanθ_1}{tanθ_2} \)

Explanation: The deflection of flow lines at interface of dissimilar soils is given by the formula,   \(\frac{k_1}{k_2} = \frac{tanθ_1}{tanθ_2}.\)

Where, θ1 and θ2 are angles made by flow line with the normal at the interface before and after the deflection respectively. K1 and k2 are the coefficients of permeability of soils 1 and 2 respectively.