why can bubbles formed in the air be square in shape not just oval or round?
478525
Everyone says that The surface tension causes the bubble to be spherical. But how? and Why? \n\nLets explain surface tension first- \nIn an air-water interface, the molecules that are close to the surface are attracted by fewer molecules of the liquid than the ones that are NOT close to the surface. The former thus, has less attractive potential energy than the latter, right?\n\nNow, for any matter (solid or liquid), attractive potential energy results in stability & repulsive energy results in instablity (common sense). \n\nSo, it is energetically unfavourable to have a surface for a liquid (or solid) as it results in loss of attractive potential energy.\n\nNow, for that reason, a bubble wants to have the lowest possible surface area to remain stable. Now, using some high level mathematics, someone found out that a sphere has the lowest possible surface area for a given volume. (it is better than a cube atleast).\n\nHence why we can see that the water bubbles and drops tend to be spherical. Due to the effect of gravity, although the drops appear oval in shape but, in the absense of gravity, all the liguid-air surfaces tend to be spherical.\n\nI hope it helped.\nHave a nice day!
524282
There are two possible reasons:\n1. A non-round object has higher surface area than a round object for same volume. This in turn could lead to higher reaction rates in portions that are not round (projections etc), finally leading to the element appearing round.\n2. The surface tension of water and buoyancy keep the element on the surface at the cost of local depression in the surface of water. Surface tension tends to make the depression round, which could make the element appear round.
377530
The shape of a drop of rain is constrained by the surface tension, which tries to give it the shape for which the surface area is minimum. For a given volume, the spherical shape has the minimum surface area. That is why rain drops acquire spherical shape.
676716
The sphere has the smallest surface area among all surfaces enclosing a given volume and it encloses the largest volume among all closed surfaces with a given surface area. For this reason, the sphere appears in nature: for instance bubbles and small water drops are roughly spherical, because the surface tension minimizes surface area.\n\nA sphere surface can also be defined as a surface formed by rotating a circle about its diameter.
22783
The bubbles are not "air" as most of the other answers claim; they are gaseous water, otherwise known as steam.  reverie's assertion about water pressure is also incorrect.  In a pot, the bubbles primarily form at the bottom of the pan because that's the hottest part of the pan and water.  The water there gets above the boiling point (212 F) and changes to steam.  At first, surface tension keeps the bubble stuck to the pan. But when enough steam is generated to make the bubble large enough, the bouancy of the bubble forces it to rise to the surface.
428530
I agree with answer one... depends on the size of the container\nThe spherical shape has the minimum surface area for a given volume (in this case for a given number of molecules, since each molecule occupies the same amount of volume).\n\nThis is why a drop of water is spherical. If we distort the drop, it “wants” to come back to its spherical shape, and the force pulling it back is what we call surface tension creating a meniscus. \n\nThis tension acts in a similar way as the stretched rubber in a balloon: if we distort the balloon and then release it, it comes back to the spherical shape.
29645
It probably is evaporating from the top. The bubbles on bottom are just more visible.
820312
Because air preasure is distributed evenly and in all directions. Notice that if you blow on a bubble it changes shape temporarily, but only as long as the preasure on it is from one side. After you stop blowing it returns to perfectly round.
815295
air bubbles look like little circles that are just floating around in the specimen area or space sometimes the air bubbles have air pockets in them to
185393
Bubbles form spheres because spheres have the smallest possible surface area for their volume. \n\nThe table below compares several different shapes and their surface areas to a sphere.\n\nSurface areas of shapes with the same volume\n\n\nShape\n Number of sides\n Volume (units3)\n Surface Area (units2)\n Area/(Area of sphere)\n (Area of sphere)/ Area\n \nTetrahedron\n 4\n 1\n 7.21\n 1.49\n 0.67\n \nCube\n 6\n 1\n 6\n 1.24\n 0.81\n \nOctahedron\n 8\n 1\n 5.72\n 1.18\n 0.85\n \nDodecahedron\n 12\n 1\n 5.32\n 1.10\n 0.91\n \nIcosahedron\n 20\n 1\n 5.15\n 1.06\n 0.94\n \nSphere\n infinite\n 1\n 4.84\n 1\n 1\n \n\nBTW - You can make a cubicle bubble\n\nUse a cube shaped bubble frame. Dip the frame completely into the bubble mix. This makes several bubble films forming a square in the middle. Dip again, but only immerse one side of the frame. A near-cubical bubble will form in the centre of the frame, surrounded by films (it may be necessary to burst a few bubbles near the centre to get just one bubble). \n\nBurst the films around the bubble one at a time. The 'cube' will be revealed to be a sphere stretched out by the films around it. \n\nAlthough a single bubble will always try to form a sphere, other shapes can be made by having several bubbles and films touching. When bubbles and bubble films meet, they always obey certain rules: \n\nFilms and edges always meet each other at equal angles, so three films meeting at an edge will be 120° and four films will be 90° apart. \nThere are never more than two films at an edge. \nThere can never be more than four edges or six films meeting at a point. \nThese rules are all consequences of the "Golden Rule of Bubbles". From these rules, it can be shown that the bubble was not a true cube, as the edges and faces did not meet in right angles. It bulged slightly.
363817
A soap bubble is spherical in shape.\n\nTo answer why a soap bubble is spherical, first we shall observe a two-dimensional phenomenon and then go to the spherical shape.\n\nConsider a rope whose ends are knotted together. Place it on the ground in any irregular shape. Equal forces are applied on each point (or small segments) of the rope so as to increase the enclosed area. Each small segment will move till the rope is in the form of a circle and the movement will be stopped after forming a circle.\n\nIf any of the force tends to move the segment in its direction, there will be exactly another force diametrically opposite to this one pulling it in the opposite direction.\nNo other shape than the circle can have this effect.\n\nIn a three dimensional view, if similar forces acting in all directions, it is not hard to visualize that the shape will be a sphere.\n\nIn a soap bubble, the air inside pushes (instead of pulling) the surface formed by soap in all directions with equal pressure.\n\n The atmospheric pressure and the surface tension of the soap bubble try to shrink the surface of the soap bubble till equilibrium is reached.
759894
Liquids like water usually have high surface tension meaning that they tend to minimize their surface area. Now this also means that stretching such a substance  (like you do with a bubble gum) is difficult. \nWhen a substance known as surfactant (used to decrease the surface tension of water) is added, the surface tension decrease and stretching the surface is more easy. It becomes now easy for the liquid to trap a certain volume of air and stretch its flat surface to form a bubble.\n(It does not mean that plain water does'nt form bubbles at all - it does so (as you observe when you pour water from a faucet in a glass) but the bubbles quickle is finished as the high surface tension forces the surface to minimum area - the flat surface.\n\nSo it is clear that whenever you decrease the surface tension of a liquid - by adding a surfactant (detergent in common household) it enhances the bubble formation by little agitation of the liquid.
941103
Because round covers don't fall in.  They are the same distance across, any way you turn them.  They always stay on top.\n\nIf it was square, it could fall in if placed at an angle or carelessly dropped by a worker.
150532
The bubbles are steam, or water vapor.  They are NOT from hydrogen and oxygen.
314648
The bubbles are the same color as the soap. They are mostly air though and there is so little "soap" in a bubble they always appear clear (or white when there is a bunch of them together.
483817
Because they started as gas/liquid, and round is the lowest energy state for a liquid.\n\nLike a raindrop.
821694
It's round because it has enough gravity to make it round, the force of gravity crushing away irregularities until a round shape is achieved. There's actually a limit in astronomy, anything with more mass then a certain amount will as a rule be round.\n\nAs for the holes, I assume you mean the craters. They are there because we're basically living in a shooting gallery of asteriods, comets, and meteors. On the moon there are no erosive forces so when one hits it the impact crater remains.