Conceptual questions regarding fluid mechanics

AI Thread Summary
Wax applied to cloth creates a waterproof barrier by filling the fabric's pores, preventing water penetration. When weighing a weightless balloon filled with water in water, the apparent weight remains unchanged, as it is effectively the same as weighing the water itself. Drinking water from the pond does not change the overall water level, as the man displaces an equivalent volume of water when he drinks. The discussions highlight the principles of buoyancy and displacement in fluid mechanics. Understanding these concepts is essential for solving related problems in fluid dynamics.
shivam01anand
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Homework Statement



I have some conceptual question in the fluid mechanics topics which has been bugging me for quite some time now.

1) When wax is rubbed on cloth why does the cloth become waterproof

2) A weightless baloon is filled with water. What will be the apparent weight when weighed in water.

3) A man is sitting on a boat which is floating in a pond. If he drinks some of the water in the pond What will be the net level of water in the pond change



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The Attempt at a Solution



For 2 i think it will decrease because of the upward upthrust.
 
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As for (1) and (3) I'm not sure where your questions points at. As for your second question, a weightless balloon filled with water is just water being limited to a confined space so, asking how much the balloon weights in water is equivalent to asking how much does water weights in water. I guess you can get the answer yourself from that, right?
 
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