what holds a cloud together and why is an airplane ride bumpy when you fly through a cloud?
87651
A cloud forms when moisture-laden warm air rises in a column expanding and cooling with higher elevation until cool enough to condense moisture and produce a visible cloud.  The cloud is not held together but forms over the rising thermals.  When a plane flies through a cloud the ride is bumpy as it hits the various thermals feeding the cloud.  You can ride in a sailplane at Elmira, NY which will glide in a circle and actually rise without power under a forming cloud.
1116707
droplets of water that condense on what are called condensation nuclei...which are small particles of matter that are suspended in the atmosphere (sand, sea salt, dirt etc)\n\nwhen the air temperature and dewpoint (the temperature the air needs to be to be "saturated") meet, the air condenses into a liquid form, which then attaches itself to the condensation nuclei....which in turn..gives you your cloud.
1063608
It does acts, otherwise the clouds would not form or if formed would leave earth's atmosphere.\nForce of gravity is directly proportional to mass of bodies( here earth and cloud) and the reciprocal of square of distance between them.\nIt comes out to be small to bring it down but not too small to hold.
378987
air pockets are simply put pockets of air that are at a different pressure than the sir surrounding them. thus there is a heavy movement of air in these pockets (hight pressure air moving in). this is generally caused by different air tempretures. when an airplane enters these pockets then the fast moving air collides with the airplane wings and gives it a sound shake. that is when you face turbulance.
679199
What you are experiencing in the roller coaster, or an airplane in turbulence, for that matter, is Newton's laws of motion, i.e.,"a body in motion will continue that motion until an outside force is applied".\n\nSo, in the case of the roller coaster, when it reaches the top of the course and starts down (that's when you feel it), your body continues its up-ward motion and direction according to Newton until a force is applied to it by way of a seat belt, or other restraint, thereby changing your body's direction.  This particular force is sometimes called a "negative g force" by astronauts and pilots, because it acts counter to gravity (g).  \n\n\nAnother way to look at it is that when the roller coaster starts down, it takes your seat with it, but your body continues going up! So it seems to you that the seat has dropped out from under you (same deal in the turbulent airplane!)\n\nNow, when the roller coaster reaches the bottom of the track, and starts back up, or the airplane climbs out of a dive, a positive g force (acting the same direction as gravity)is created. Then, you are jammed down in your seat, or, as Newton would explain, "the seat you are in is applying an upward force on your body, which wants to continue down in the direction it was going!\n\nAin't physics fun?
854216
Since a cloud is made up of lots of small droplets of condensed water (or, in the case of some clouds, the condensed water freezes into ice crystals), if you were able to "shake" the cloud (get the water droplets moving around randomly) they would collide and form larger water drops.  These drops should then eventually become heavy enough to drop from the sky as rain.\n\nWikipedia has a pretty good article on clouds.
799074
How scientific do you want it?\n\nBasically, air circulates the earth.\n\nThis air has different temperatures in different places.\n\nThe different temperatures cause different pressures of air masses.\n\nBecause of this air flows around air masses due to the pressure gradient between different masses.\n\nThis air flow drags air of even higher temperature differences into contact.\n\nDifferent air temperatures meet causing one to rise over the other, as this rising air goes up it cools and causes clouds (These areas where air masses join are the fronts on a weather map).\n\nThese clouds then produce rain.\n\nThat rain changes temperatures, more air masses are drawn into contact, and the cycle repeats.
601596
Clouds form when the invisible water vapor in the air condenses into visible water droplets or ice crystals. This can happen in three ways.\n\n1. The air is cooled below its saturation point. This happens when the air comes in contact with a cold surface or a surface that is cooling by radiation, or the air is cooled by adiabatic expansion (rising). This can happen\n\nalong warm and cold fronts (frontal lift), \nwhere air flows up the side of a mountain and cools as it rises higher into the atmosphere (orographic lift), \nby the convection caused by the warming of a surface by insolation (diurnal heating), \nwhen warm air blows over a colder surface such as a cool body of water. \n2. Clouds can be formed when two air masses below saturation point mix. Examples are breath on a cold day, aircraft contrails, and Arctic sea smoke.\n\n3. The air stays the same temperature but absorbs more water vapor into it until it reaches saturation.\n\nThe water in a typical cloud can have a mass of up to several million tonnes. However the volume of a cloud is correspondingly high, and the net density of water vapor is actually low enough that air currents below and within the cloud are capable of keeping small droplets suspended. As well, conditions inside a cloud are not static: water droplets are constantly forming and re-evaporating. A typical cloud droplet has a radius on the order of 1 x 10-5 m and a terminal velocity of about 1-2 cm/s. This give these droplets plenty of time to re-evaporate as they fall into in the warmer air beneath the cloud.\n\nMost water droplets are formed when water vapor condenses around a condensation nucleus, a tiny particle of smoke, dust, ash, or salt. In supersaturated conditions, water droplets may act as condensation nuclei.\n\nWater droplets large enough to fall to the ground are produced in two ways. The most important is through the Bergeron Process, theorized by Tor Bergeron, in which supercooled water droplets and ice crystals in a cloud interact to produce the rapid growth of ice crystals, which precipitate from the cloud and melt as they fall. This process typically takes place in clouds with tops cooler than -15°C. The second most important process is the collision and wake capture process, occurring in clouds with warmer tops, in which the collision of rising and falling water droplets produces larger and larger droplets, which are eventually heavy enough to overcome air currents in the cloud and the updraft beneath it and fall as rain. As a droplet falls through the smaller droplets which surround it, it produces a "wake" which draws some of the smaller droplets into collisions, thus perpetuating the process. This method of raindrop production is the primary mechanism in low stratiform clouds and small cumulus clouds in trade winds and tropical regions, and produces raindrops of several millimeters diameter.\n\n \nThis wave cloud pattern formed off of the Île Amsterdam in the far southern Indian Ocean.The actual form of cloud created depends on the strength of the uplift and on air stability. In unstable conditions convection dominates, creating vertically developed clouds. Stable air produces horizontally homogeneous clouds. Frontal uplift creates various cloud forms depending on the composition of the front (ana-type or kata-type warm or cold front). Orographic uplift also creates variable cloud forms depending on air stability, although cap cloud and wave clouds are specific to orographic clouds.
334289
I assume you mean a fly in the car with you.\n\nThe reason is inertia.  You, the car, the fly, and all of the air in the car share the same inertia, which means relative to each other, you are motionless.  Open a window, and inertia and air pressure differentials will circulate air through the car, and hopefully suck the little bugger out so you can drive in peace.
1166276
Clouds are mists of water droplets that have condensed out of water vapour at "dewpoint", which is dependent on temperature, pressure, and humidity.\n\nThere is no intelligence or knowing involved.\n\nClouds don't fly, they are blown by the wind.
714393
The water's in a vapor form which makes it much much lighter than if it were in liquid form, and there are air currents within clouds that keep the vapor circulating around and are able to hold the water up against gravity.  It's when water vapor starts forming droplets that it gets too heavy for clouds and we get rain, hail, etc.
186119
rain comes from clouds. clouds are actually water vapour floating in air. when they become really condensed due to a drop in temperature then they form large drop of water which cant stay afloat and so rain happens.
48985
airplane wings work because of their curvature - the upper surface of the wing is more curved than the lower surface, so air moving over the top of the wing has to take a longer path.  \n\nthis longer path causes the air to thin out over the top surface of the wing, and this leads to a lower pressure on the top surface.  the higher-pressure air on the underside of the wing pushes the wing upwards into the lower-pressure region, just like the higher pressure inside a balloon pushes the balloon outwards into the lower-pressure atmosphere.\n\nanyway, i think you can think about a leaf on a windshield as acting like a wing of sorts.  air will flow faster over the upper surface of the leaf but stay trapped underneath.  if the leaf is solid, then the pressure differential pushes outward on the leaf, away from the windshield.  \n\non the other hand, if there is a slit in the leaf, then the higher-pressure air underneath can move through the slit and equalize the pressures, so there is less force on the leaf pushing it away from the windshield.\n\nas for holes, perhaps if the holes were big enough, you would no longer have the smooth ("laminar") flow over the surface, and instead get turbulent air that causes a vortex to form.  \n\nvortices are lower pressure areas so that might suck the leaf off.  or, a big hole might cause an edge of the leaf to flip up into the airstream and catch some of the air, forcing it down under the leaf and pushing it off the windshield - whereas a slit might still allow the air to flow smoothly over the leaf yet still equalize the pressure.\n\ni'm totally guessing, but i guess it's a reasonable theory.
707708
The droplets that make up clouds freeze all the time, but clouds don't freeze into solid blocks because the particles are too dispersed. In fact, most of the high-altitude clouds you see are made up of frozen droplets.
479562
Clouds are formed when water vapour in the air is cooled and condenses as part of the water cycle. Clouds consist of billions of tiny water droplets (and even ice crystals) floating in the sky and appear in a variety of shapes and sizes depending on how and where they formed.
606380
Clouds are tiny droplets of water that have condensed on condensation nuclei such as pollen, dust, ash, & pollution in the troposphere.\n\nB/c they are very tiny and independant of each other, they tend to be suspended. This is due to various things such as updrafts, winds, etc. They are very lightweight. Only when they begin to start growing in size will gravity take over & they start to fall as rain.
922889
Because air at ground level and a significant distanace above is rarely saturated - when it is, fog forms - which is a cloud on the ground. It has to be saturated a significant distance above ground or else you only get shallow areas of ground fog or dew/frost (if it is unsaturated say 50-200 feet above ground).\n\nBases of what we normally consider to be clouds rarely touch the ground because rising air motion is required to saturate the air and form the cloud. If it has to rise to do that, it cannot occur on the ground - though such clouds can be advected to a higher location and perhaps reach ground level there - or as is more common, the rising motion occurs up a slope with a cloud forming at some point along it.