Linked Questions

2
votes
1answer
542 views

Why do denser things sink? Detailed justification needed [duplicate]

I would like a detailed explanation and justification if possible regarding the topic. I would like to know what happens at an atomic level. Most of the answers I have found were very basic and did ...
0
votes
1answer
117 views

Making sense of the Buoyancy force [duplicate]

I was reading about how to find the buoyancy force when I came across this explanation: Imagine a box submerged in a tank of liquid. The distance from the surface of the liquid to the bottom ...
107
votes
8answers
43k views

Why does a helium filled balloon move forward in a car when the car is accelerating?

I noticed that when I had a helium filled, latex balloon inside of my car, it moved forward in the cabin as I accelerated forward. The faster I accelerated forward, the faster the balloon went from ...
11
votes
8answers
2k views

Can a ship float in a (big) bathtub?

I am confused. Some sources say it is possible at least theoretically ( http://www.wiskit.com/marilyn/battleship.jpeg ) and some say it is not true ( http://blog.knowinghumans.net/2012/09/a-...
4
votes
1answer
7k views

Derivation of Archimedes' principle

It is my understanding that upthrust from a liquid on a body is due to pressure difference on the top of the body and the bottom of the body. How, then, is this fact used in order to derive/work out ...
0
votes
3answers
5k views

If we dropped an object into the Pacific Ocean, would it completely sink to the bottom of the ocean floor or not?

Obviously if the density of the object is smaller than the density of water it would not sink at all. But I was thinking that, even if the density of the object is greater than the density of water, ...
4
votes
2answers
2k views

Why is Buoyant Force $V\rho g$?

For a submerged object, buoyant force ($F_b$) is defined as: $$F_b = V_{\text{submerged}} \times \rho \text{ (density)} \times g \text{ (gravitational constant)}$$ Conceptually, the buoyant force ...
3
votes
2answers
1k views

The Spinning Log “Perpetual Motion” problem, and my attempt at a solution

So I was introduced to this "perpetual motion" riddle a few weeks ago. The problem goes like this: we all know perpetual motion machines are not possible, but this riddle seems like it should work as ...
0
votes
4answers
1k views

Buoyant force in an elevator

I can't understand why buoyant force exerted by the liquid on a ball attached to a rope in a box having liquid of density $p$ moving in an elevator moving with acceleration $a$ has buoyant force as, $...
3
votes
2answers
88 views

Fluid exerting buoyant force on itself?

I was just wondering, if I took some infinitesimal section of a fluid and constructed a free body diagram on it, would it experience a buoyant force from the rest of the fluid it is part of to cancel ...