Strenght of Materials

When the retained material is subjected to some superimposed or surcharged load, the total horizontal pressure due to surcharged load is (where p = Intensity of the supercharged load)
A. `p xx (1 - sin phi)/(1 + sin phi)`
B. `p xx (1 + sin phi)/(1 - sin phi)`
C. `p xx (1 - cos phi)/(1 + cos phi)`
D. `p xx (1 +cos phi)/(1 - cos phi)`

Answer : Option A

Explanation :