what physics principle explains the removal of water from the clothes in a spin dyer? explain.?

Answer 1

I'm not sure that spin dyers would work all that well --- the dye would probably come out, with the water. Spin dryers, on the other hand, are certainly practical and extremely useful.

While one could assert that only one physics principle is really relevant as far as the water is concerned, that of INERTIA (see below), another (Newton's 2nd Law of Motion, "F = Ma") is also involved, to some extent, in "removing the clothes from the water."

The clothes can't get out of the drum of the spin dryer, because the holes in the drum's wall are too small. Friction keeps them in contact with the drum itself. The clothes are being rotated and therefore continually ACCELERATED towards the centre of the drum by a CENTRIPETAL FORCE provided by the drum's curved outer wall. The drum has to be strong enough to do this, which is a factor in its design. The stresses in the drum go up as the square of the spin rate. That is why spin rate limitations must be put on any rotating devices, in order to avoid catastrophic failures. For example, one occasionally hears of an aircraft engine breaking apart in mid-flight, due to a microscopic and unnoticed flaw which has weakened it to the extent that it can't hold together under the enormous centripetal accelerations implied by operational spin rates.

How can you convince someone that the parts of rotating things ARE accelerating in inertial space, and therefore that there MUST BE some force operating (by Newton's Second Law, "F = Ma" and all that)? It's because UNACCELERATED motion IS straight-line motion with the same speed at all time. Anything that's NOT doing that is, ipso facto, accelerating, and to accelerate TO THE LEFT (say), you need to have a FORCE TO THE LEFT to ensure this.

Meanwhile the water, being a liquid, isn't so constrained since there are some holes in that same outer wall. That means that the water can get out. It essentially emerges from the hole at the outer wall of the drum TANGENTIALLY, since the other (and main?) scientific principle involved is that moving things continue at the same speed in the same direction, UNLESS they're acted on by a force. (Newton's First Law, or the LAW OF INERTIA.)

So, basically, the two physics principles involved in the spin dryer are Newton's First and Second Laws of Motion.

Live long and prosper.

P.S. There's an incredible amount of confusion in this area of rotational motion, generally caused by people not realizing that what they call "centrifugal force" is essentially a calculational device enabling one to solve a limited class of dynamical problems as "static," in effect, by treating a rotating frame of reference as though it were NOT rotating. This does NOT mean that there is actually a REAL radially directed force "accelerating" or "forcing" something outwards i.e. in the radially directed direction.

(If the complete situation doesn't even look "static" --- i.e.an "unchanging configuration" --- in any one particular rotating frame, something additional, the so-called "Coriolis force," has to be introduced as well, in order to be able to describe what's going on in what is then a rotating frame with internal kinematical and dynamical motion in IT. Furthermore, if the rotating frame you've chosen happens to have a variable angular velocity itself, there are yet more terms. You can see how complicated it can become, introducing yet more "artificial force terms" to make sense of yet more rotational complications. Sometimes that's inescapable --- treating a rocket's motion with respect to the Earth's surface as part of a rotating frame, for example, we observing humans ourseves rotating with the Earth's surface.

But to understand what's happening FUNDAMENTALLY, it's best to return to the bedrock of Newtonian mechanics in inertial space, and understand that "real forces" and "real accelerations" are needed to make curved paths IN THAT. I've had countless beginning students who seem to have been previously given "centrifugal force" as some mantra to apply in rotating situations, but who have been simply unable to use it to help work out relatively simple problems involving rotation in a gravitational field. Double counting, or cancelling, is a frequent problem, because they've apparently never been clearly taught how "centrifugal force" involves using a mathematical expression that ultimately arises from Newton's own bedrock equations, when the latter are applied to rotating coordinate systems.)

Many engineers are prone to think of "centrifugal force" as real, rather than to think in the scientifically unassailable terms of Newton's Second Law of Motion in a non-rotating and therefore inertial frame.

But it's not just engineers: there's a very fine pure mathematician at my university who is nevertheless convinced of the following. That is that if I whirl a weight on a string around my head, and then cut the string, the weight will fly out ALONG THE DIRECTION THE STRING LAST HAD at the moment it was cut. According to him, that's because I'm cutting the tether, but "not cutting the centrifugal force," which he insists must still oparate. (!!) What's more, no amount of demonstration will convince him; he says that letting go of the string is different, since I'm not "cutting it." Lord help us!

The immediately previous two answers to mine are simply wrong in suggesting that something like "outward force" or "outward acceleration" are taking place. They're simply NOT, NOT, NOT. In contrast to that, the immediately following answer has it quite right.

To underline the true situation again : INERTIA makes the water leave the drum TANGENTIALLY, WITH NO ACCELERATION. The clothes ARE ACCELERATING inwards towards the centre of the drum. They ARE moving away increasingly from any given straight line tangent, constrained from GOING TANGENTIALLY as they are by that outer wall, because it's built strongly enough to withstand the stresses that rapid rotation implies.

Answer 2

I think this is covered by Centrifugal Acceleration. Think of a sling, David and Goliath style. An object moving in a circle (e.g .water in a spin dryer) accelerates away in a direction tangent to the arc of the circle. So if you cut the string while spinning a sling, or poke holes in the receptacle holding the water, the spinning object will fly away.

Answer 3

The water and the clotes are pushed stressful against the wall of the spinning washing device or spin-dryer via the centrifugal rigidity--the outward push you experience in a rotating physique of reference. Small holes interior the wall enable water to flee and drain off, yet shop the clothing in.

Answer 4

The physical principle is that the fundamental property of inertial mass is that it resists changes in its motion....meaning that everything tends to travel in a straight line unless a force is applied to it.

The water particles tend to go straight but the direction of the clothes is constantly changing. Therefore they both separate. That is why the walls of the dryer have little holes in it. The holes allow the water to go in a straight line but not the clothes.

Answer 5

Centrifugal force. The rotating tub is forcing all objects in the tub away from the centre . The side of the tub opposes this movement except where the object is small enough to fit through the small holes. So the water is being pushed by the Centrifugal Force out of the tub

Answer 6

Centripetal acceleration, when the clothes are spinning the water goes out, but your clothes remain inside the dryer.