Answer:
Vr = 20 [km/h]
Explanation:
In order to solve this problem, we have to add the relative velocities. We must remember that velocity is a vector, therefore it has magnitude and direction. We will take the sea as the reference measurement level.
Let's take the direction of the ship as positive. Therefore the boy moves in the opposite direction (Negative) to the reference level (the sea).
![V_{r}=30-10\\V_{r}=20 [km/h]](https://tex.z-dn.net/?f=V_%7Br%7D%3D30-10%5C%5CV_%7Br%7D%3D20%20%5Bkm%2Fh%5D)
The pressure drop in pascal is 3.824*10^4 Pascals.
To find the answer, we need to know about the Poiseuille's formula.
<h3>How to find the pressure drop in pascal?</h3>
- We have the Poiseuille's formula,

- where, Q is the rate of flow, P is the pressure drop, r is the radius of the pipe, is the coefficient of viscosity (0.95Pas-s for Glycerin) and l being the length of the tube.
- By substituting values and rearranging we will get the pressure drop as,

Thus, we can conclude that, the pressure drop in pascal is 3.824*10^4.
Learn more about the Poiseuille's formula here:
brainly.com/question/13180459
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<span>What is the process of conduction in terms of particle movement chocies
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