From the given value v = 20 m/s v = jet velocity plate velocity (u) = 10 m/s area of jet = .01 m2 density of water = 1000 Kg/m3 force developed on plate F=ρa(v–u)2 =1000×0.01(20−10)2 =1000×.01×100=1000N second case blade are in series force F=ρav(v−u)