Understanding the Net Force on a Snorkeler's Eardrum

Thread starter guyvsdcsniper
Start date Apr 18, 2021
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Force Net Net force

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The discussion centers on calculating the net force on a snorkeler's eardrum by considering both internal and external pressures. It highlights the importance of recognizing that pressure differences between the inside and outside of the ear create forces acting on the eardrum. The participant initially calculated the force from internal pressure but questioned whether external pressure should also be factored in. Understanding the balance of these forces is crucial for accurately determining the net force. Clarifying the role of external pressure is essential for solving the problem correctly.

Apr 18, 2021

guyvsdcsniper

Homework Statement: What is the net force on the ocean snorkeler of Question 1 if the pressure inside her ear is 1.0 atm (=101.3 kPa)? An adult's eardrum has a typical diameter of 8.0 mm

Relevant Equations: P=F/A

Can someone help me understand what I did wrong when solving this problem?

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Apr 18, 2021

TSny

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You found the force on the eardrum due to the pressure inside the ear. Is there also a force due to pressure outside the ear?

Thread 'Chain falling out of a horizontal tube onto a table'

My attempt: Initial total M.E = PE of hanging part + PE of part of chain in the tube. I've considered the table as to be at zero of PE. PE of hanging part = ##\frac{1}{2} \frac{m}{l}gh^{2}##. PE of part in the tube = ##\frac{m}{l}(l - h)gh##. Final ME = ##\frac{1}{2}\frac{m}{l}gh^{2}## + ##\frac{1}{2}\frac{m}{l}hv^{2}##. Since Initial ME = Final ME. Therefore, ##\frac{1}{2}\frac{m}{l}hv^{2}## = ##\frac{m}{l}(l-h)gh##. Solving this gives: ## v = \sqrt{2g(l-h)}##. But the answer in the book...

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