Tap Water Flow Reduction: Why Does Distance Matter?

AI Thread Summary
The discussion explains that the reduction in the cross-section of water flow from a tap as distance increases is due to the acceleration of water as it falls. The mass flow rate remains constant, but the speed increases, causing the cross-section to decrease. Surface tension helps maintain a narrow stream shape rather than allowing it to fall straight down. Participants express appreciation for the insightful answers provided. Overall, the thread highlights the physics behind tap water flow dynamics.
Jayse_83
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Hi,
Please could someone explain why it is that the cross section of water emerging from a tap decreases with tap distance ... is it due to air resistance acting to form some kind of aerodynamic shape? any thoughts would be much appreciated!
 
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It's simply that the water accelerates as it falls. The rate (mass per second) at which water flows remains the same throughout the stream, but since the speed increases as it falls, the cross-section must decrease. The stream retains a narrow shape (instead of falling straight down like rain) due to surface tension holding things together.
 
wow! great answer, thanks Doc :D
 
Jayse_83 said:
wow! great answer, thanks Doc :D
You want to know what I love best about this place? Too bad; I'm going to tell you anyhow. It's that people like you ask questions that never entered my mind in my entire life until I see them here, and then I want to know the answer as well. And I get one. This whole site rocks! :approve:
 

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