Hydro-dynamic pressure on dam due to earthquake, acts at the height of :(H is the depth of water)
1
\(\frac{4H}{3 \pi}\) above the base
2
\(\frac{3H}{4 \pi}\)above the base
3
\(\frac{3H}{4 \pi}\) below the water surface
4
\(\frac{4H}{3 \pi}\) below the water surf