I provided to think the the form of an object determines its capability to rise (boat-shaped objects are much more likely come float, and also spheres tend to sink). But my friend, who is fond of making me watch stupid, take it me come the neighborhood lake confirmed me a sphere that floated and also a boat-shaped object made out of iron the sunk.

You are watching: What do the floating objects have in common?

Is it based on the mass? I"m not sure that is possible, since I"ve viewed really hefty things (like plane carriers) float, and also really light things (like my friend"s steel boat) sink.

What property of particular objects allow them come float, if any?


thickness buoyancy fluid-statics
re-publishing
mention
improve this question
monitor
edited Oct 9 "17 at 20:24
*

Qmechanic♦
156k3030 gold badges379379 silver badges18521852 bronze badges
inquiry Nov 4 "10 in ~ 22:21
*

Justin L.Justin L.
5,83255 gold badges4040 silver- badges5050 bronze title
$endgroup$
2
$egingroup$ Aeroplanes don't fly because of buoyancy, however due come the lift force. However it functions for balloons. $endgroup$
–user68
Nov 4 "10 in ~ 23:52
add a comment |

9 answers 9


active oldest Votes
9
$egingroup$
Actually, the prize is a bit much more subtle than just density. The principle the is behind floating objects is Archimedes" principle:

A liquid (liquid or gas) exerts a buoyant force, opposite apparent gravity (i.e. Gravity + acceleration that fluid) on an immersed object that is equal to the load of the displaced fluid.

See more: Which Of The Following Is An Example Of A Learned Behavior? Learned Behaviors (Article)

Thus, if you have an object totally immersed in a fluid, the complete force it feels is offered by (positive sign method down):

$$F = extgravity + extbuoyancy \= ho_ extobject V g - ho_ extfluid V g \= ( ho_ extobject - ho_ extfluid) V g$$

Thus, if the average thickness of the object is lower than the of the water, that floats. If the object is partially immersed, to calculation the buoyant pressure you have to take into consideration just the immersed volume and also its mean density:

$$F = ho_ extobject V g - ho_ extfluid V_ extimmersed g$$

Note that once I to be talking about density, ns was talking around the average density of the object. The is that is total mass separated by that volume. Thus, a ship, also if the is made the end of high-density iron that is full of air. That air will lower the typical density, together it will boost the volume considerably while keeping the weight nearly constant.

If you want to know this better you can provide the following trouble a try :)