# Siphoning A Clogged Sink (Bernoulli's Principle)

• GDGirl
In summary, the siphon tube rises 50 cm above the bottom of the sink and then descends h=93 cm to a pail as shown above. The siphon tube has a diameter of 1.57 cm. Assuming that the water enters the siphon with almost zero velocity, calculate its velocity when it enters the pail. The velocity when the water enters the pail is 5.298 m/s.

## Homework Statement

You need to siphon water from a clogged sink. The sink has an area of 0.496 m2 and is filled to a height of 4.0 cm. Your siphon tube rises 50 cm above the bottom of the sink and then descends h = 93 cm to a pail as shown above. The siphon tube has a diameter of 1.57 cm.
a. Assuming that the water enters the siphon with almost zero velocity, calculate its velocity when it enters the pail.
Help: Use Bernoulli's Principle.

https://wug-s.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?cc/Knox/phys130a/spring/homework/18/02/HW19_5.jpg [Broken]

## Homework Equations

P1+1/2$$\rho$$v12+$$\rho$$gy1= P2+1/2$$\rho$$v22+$$\rho$$gy2
equations derived from similar examples in class:
v1=sqrt(2gh) when v2 (or whatever sub number theother velocity is) is negligible.
or v1=sqrt((2gh)/(1-(A12/A22)))

## The Attempt at a Solution

I have tried everything I can think of. I tried finding the cross-sectional area of the tube and plugging that area in as A1 in the final equation I listed. I square that, divide it by the square of the area of the sink, subtract that from one and divide my answer for 2gh (2*9.8*(.5+.93)=28.028) by that and take the square root and I get 5.298 m/s which is incorrect.
When I simply plug my numbers into sqrt(2gh) I get 5.294, which is also incorrect.
Then, I've tried plugging numbers into the entire equation for Bernoulli's Principle. However, I was kind of BSing the pressures since I'm not sure what the pressure would be at the start of the tube and what it would be at the end of the tube. So I'm disregarding that attempt.
So generally, I'm completely stuck on this, can someone give me a hand?

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Can you not just use conservation of energy?

Rather, if I understood it better. I don't know how that applies to what I'm working on here (I tend to have trouble making connections between things like that)
It's not like our work gets checked. I'm just going with the equation that the help suggests.

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(2*9.8*(.5+.93)=28.028)

Isn't the difference in height just .43 m?

Yes, I did.
Since I need the velocity at the bottom of the tube... I wasn't sure if I should just use one or the other of the heights given or take the height at the entirety of the tube... I'll try the difference of heights though. :/

Oh, that worked out perfectly... I didn't think about taking the difference of the height ^^'

## What is Bernoulli's Principle and how does it relate to siphoning a clogged sink?

Bernoulli's Principle states that as the speed of a fluid increases, the pressure decreases. This principle is crucial in understanding how siphoning works. In a clogged sink, the fluid (in this case water) is forced to move at a higher speed through a narrow opening, creating a lower pressure behind the obstruction. This pressure difference allows the water to move from the higher to the lower pressure area, effectively siphoning the water out of the sink.

## Can any liquid be siphoned using this principle?

Yes, any liquid can be siphoned using Bernoulli's Principle as long as there is a source of higher pressure and a lower pressure destination. However, the effectiveness of the siphon may vary depending on the density and viscosity of the liquid.

## What are the common reasons for a clogged sink?

A clogged sink is usually caused by a buildup of debris, such as food particles, grease, and hair, in the drain pipes. The debris can create an obstruction that hinders the flow of water and causes it to back up in the sink.

## How can siphoning a clogged sink be done safely?

Siphoning a clogged sink can be done safely by ensuring that the siphon is only initiated with a clean source of water. This means that there should be no debris or contaminants in the water being siphoned. It is also important to use clean equipment and to avoid inhaling or ingesting the liquid being siphoned.

## Are there any potential risks involved in siphoning a clogged sink?

Yes, there are potential risks involved in siphoning a clogged sink. These include inhaling or ingesting the liquid being siphoned, as well as exposing oneself to harmful chemicals or bacteria that may be present in the sink or drain pipes. It is important to take necessary precautions and follow proper safety measures when siphoning a clogged sink.