Entrance

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Near the entrance we can learn a lot from Bernoulli:

$$p_1 + {\textstyle\frac{1}{2}} \rho V_1^2 + \rho g h_1 = p_2 + {\textstyle\frac{1}{2}} V_2^2 + \rho g h_2$$

Exercise:

Explain why $p_{\rm kin,B'} \approx p_{\rm kin,B} \approx p_{\rm kin,B''}$ although $V_B \ne 0$ while $V_{B'} = V_{B''} = 0$.

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Exercise:

Which one is larger:

• $p_{A'}$ or $p_{A''}$?
• $V_{A'}$ or $V_{A''}$?

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