May one hang a wet raincoat on a washing line? 

It is known that Chazal instituted certain decrees in order to prevent people from making mistakes. [1] They predicted that if people would see someone hanging wet clothes on a washing line on Shabbos, they might think that the clothes were also laundered on Shabbos and may wash clothing themselves. They therefore forbade hanging wet clothes on washing lines.

Another common rule is that when a decree was to prevent a Torah violation, the decree applies itself even to the darkest of rooms, where no outside individual could possibly see. îøàéú òéï àñåø àôéìå áçãøé çãøéí.

Therefore, wet clothing may not be hung to dry on outdoor or indoor washing lines, like over a bath. Even a raincoat wet from the rain, may not be hung up over the bath. However, one is permitted to put it in its normal place, for example, drape it over a chair, or place it on a hangar and hang it on a door. [2] 

Does it make a difference whether it got wet from the rain or it fell into a puddle? 

It is immaterial whether it got wet from the rain or because it fell into a puddle. So much so, the halacha is that even clothes moist from sweat may not be hung up on the line, for the same reason. [3] It does not mean that wet clothing must be bunched up and thrown in the corner, rather as mentioned before, it may be draped over a chair etc, something one would normally do even if the clothes were not wet. 

Why should it be ossur to hang outdoors when wet from rain, don't people realize that it was raining? 

It is a very good question, but I think the answer is as follows. Halachically one may leave laundry on a washing line before Shabbos and need not remove them before Shabbos. [4] Probably Chazal were concerned with washing that appears on the line during Shabbos that was not visible before Shabbos. Seeing a clothing item on a line during Shabbos raises suspicion it was laundered. Also, Chazal's decrees cover all instances, even though some instances could rationally be explained. 

If a sock landed inside a washing bowl, what is its status?

The Rama [5] teaches us that wet clothing is muktze, lest one will wring out the water. So if one’s sock or shirt lands into a bowl of water the sock is muktze. The Rama continues that this is only with clothes one is particular about being wet, but clothes that are normally wet, or clothes one does not care about being wet, are not muktze, since there is no reason to suspect that one will squeeze out the water.

Therefore, a floor rag is not muktze when wet, because one does not mind it being wet. It would seem that the same would apply to a wet towel. [6]

 How is one supposed to put wet clothing on a chair etc, if the clothing is muktze?

The Chofetz Chayim [7] says that when one removes wet clothing, one may put them in the permitted places, but after removal they are muktze. So when entering from the rain, make sure to put your drenched socks, pants etc. over a chair before putting them down, because  once you put them down, there is not much you can do. According to the Mishna Berura one may handle muktze b'gufo, so you would be permitted to lift wet clothes by carrying them between your elbows etc. but try and avoid that because it is not accepted by all opinions.

 How is one supposed to wipe up a mess on the floor on Shabbos?

We have two problems here, one, not to use something that would become muktze, because of mevatel k’li meheichano as mentioned in previous shiurim. The second is that one may not use a cloth that one would normally squeeze. Therefore one should use either paper napkins or rags which one does not usually squeeze out, and thereby avoid the two problems mentioned.

For example, if coke spilled on the floor one may wipe up the mess with towels, paper napkins and rags. If the floor is sticky from the spill, one may pour some water directly onto the floor and wipe it with a towel or rag. Since the towel or rag get soiled from this action, it is not libun (laundering) when the towel or rag come into contact with the water on the floor. 

When lifting the wet towels or rags from the floor, is there not a problem of squeezing liquid in the process?

 Indeed one should attempt to leave a corner dry with which to lift the towels. If not possible, because it is sopping wet, one should try lifting it with an item such as a fork by slipping it beneath the towel and lifting it so as not to squeeze the liquid.

 

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