Total force due to wave action on a gravity dam acts at a height of
1
\(\frac{{{{\rm{h}}_{\rm{w}}}}}{2}\) above the reservoir surface
2
\(5\frac{{{{\rm{h}}_{\rm{w}}}}}{2}\) above the reservoir surface
3
\(\frac{3}{8}{{\rm{h}}_{\rm{w}}}\) above the reservoir surface
4
\(\frac{2}{3}{{\rm{h}}_{\rm{w}}}\) above the reservoir surface