1. The problem statement, all variables and given/known data Hello,Could you please lend me a hand with this problem?I would really appreciate it. Question: Their Answer: KL=2*0.75(2 elbows) D=5*10^-2 m ;f=0.001(fanning friction factor) Assumptions I made: Point 1 which is at the top of the liquid in the tank: h1=23 m; u1=0m/s(neglected due to Area differences) P1=0 gauge(atmos press) Point 2 which is at the mouthpiece of fountain: h2=0m(datum); u2=? P2=0 gauge(atmos press) 2. Relevant equations We know bernoulli for losses with fanning friction factor P1/ro*g+h1+u1^2/2*g=P2/ro*g+h2+u2^2/2*g +delta hloss where delta hloss=K*u^2/2g where K=f*4*L/D+Ki where Ki=sum of K in our case 2*0.75(2 elbows) where f is fanning friction factor. 3. The attempt at a solution P1/ro*g+h1+u1^2/2*g=P2/ro*g+h2+u2^2/2*g +delta hloss As we made the assumption in first step.This can be rewritten as: h1=delta h loss =>h1=K*u^2/2*g h1=(f*4*L/D+Ki)*u^2/2g =>u=sqrt(h1*2g)/(f*4*L/D+Ki) and substituting values in this formula gives u=10.05 m/s However their answer is 9.0 m/s I do not understand 1) why they did Ki=0.5+2*0.75, from where comes that "0.5"? 2)From where comes that "1+" in their sqrt formula 2)Why they picked L=20+10+2 Thank you in advance , much appreciated.