Fluid Dynamics: Using Bernoulli's equation and Volume Flow Rate

AI Thread Summary
The discussion revolves around a fluid dynamics problem involving water flow from a faucet, using Bernoulli's equation and the continuity equation. The initial velocity of water is calculated at approximately 1.70 m/s, while the final velocity at a narrowed diameter of 10 mm is found to be about 3.82 m/s. The height below the faucet where the water stream narrows is determined to be approximately 0.597 meters. The participant expresses uncertainty about the accuracy of their calculations but believes the answer seems correct. Overall, the application of fluid dynamics principles is effectively demonstrated in solving the problem.
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Homework Statement


Water flowing out of a 15.0mm -diameter faucet fills a 1.50 L bottle in 5.00s. At what distance below the faucet has the water stream narrowed to 10 mm in diameter?


Homework Equations


Bernoulli's equation: P_1+pgh+1/2pv^2=constant
Q(volume flow rate)=vA
Continuity Equation: A_1(V_1)=A_2(V_2)

The Attempt at a Solution



Finding the intial velocity of the fluid:
A_1=pi(0.0075m^2)= 1.77*10^-4 m^2
Q=1.5L/5.00s=0.3L/s --->Q=vA (Rearrange the equation)--> v_1=Q/A_1= 0.0003m^3/s / 1.77*10^-4m^2 = 1.69765..m/s

Finding the final velocity of the fluid:
A_2=pi(0.005m^2)=7.85*10^-5 m^2
v_2=Q/A_2= 0.0003/7.85*10^-5 m^2 =3.81971...

Finding the height:
1/2pv_1^2=pgh+1/2pv_2^2
h=(1/2*p*v_1^2)-(1/2*p*v_2^2)/pg---> (p cancels out)
=(1/2*v_1^2)-(1/2*v_2^2)/g=0.597m

But, I feel that I must have done something wrong in my calculations. I don't know if my answer makes sense.
 
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Looks correct to me.
 
Okay,thanks!
 
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