I need help with my lab report. I performed static electricity lab and need help

Question

I need help with my lab report. I performed static electricity lab and need help with answering the questions completely. I have bolded my answers, but I need explanation as to why that result have occured for the appropriate questions. Thank you so much for your help!!!

A metal ring is suspended. Charge the polyethylene strip with the wool cloth and bring it closer to the left side of the ring. Be careful to not let the polyethylene touch the ring.

a.) What happens to the metal ring when it is brought into proximity of the charged polyethylene?
The metal ring is coming closer to the charged polyethylene strip. Thus, the metal ring is attracted towards the negatively charged polyethylene strip.

b.) Describe what happens to the charges inside the metal ring when the polytethylene is in proximity. Is the metal ring acquiring a net charge in this instance?

c.) Rub the vinyl strip vigourously with the cotton cloth and bring the vinyl into close porximity with a very thing stream of water from the sink. Describe the results. Whys does the water act the way it does? Does the water gain a net charge from the vinyl?
The water goes toward the vinyl strip when the vinyl strip is brought closer to the water. Water is attracted to the vinyl strip.

Explanation / Answer

(a) When the polyethylene strip is rubbed by the wool cloth, it acquires some electrons from the cloth and becomes negatively charged. Due to the charge induction, positive charge is induced on to the ring and hence they attract each other.

(b) Yes, this method is called the electrostatic induction in which static charges can be generated in a material by bringing an electically charged object near to it. In our case, the ring is the material and charged object is the polyethylene strip.

For example, if a positive charge is brought near the object, the electrons in the metal will be attracted toward it and move to the side of the object facing it. When the electrons move out of an area, they leave an unbalanced positive charge due to the nuclei. This results in a region of negative charge on the object nearest to the external charge, and a region of positive charge on the part away from it. These are called induced charges. If the external charge is negative, the polarity of the charged regions will be reversed (example is the present problem).

(c) water (H2O) is a polar molecule. the stream of water will bend towards the strip. If the charged rod is positive, the stream of water will be passively polarized: the mobile charges in the water which chose to move towards the charged rod will be of whichever polarity which is attracted to positive charge, i.e., negative charges. Like charges (positive) will be repelled to "the other end", probably up in the tank or tubes supplying the water.

If the rod is charged negative, the water will be polarized in the opposite direction: positive charge near the negative rod.

Either way, the part of the water near the rod is attracted to the rod. The part farther away is repelled, but then, it is farther away so the force is weaker. Net attraction results in solid objects. The water is not even a rigid object, so the part nearby simply responds to local attraction.

The water's passive polarization is "induced" by the electric field from the charged rod. The water is not like a magnet with its own intrinsic polarization. It is more like a piece of iron, "passively magnetic", in which magnetic polarization is temporarily induced by the magnetic force from a nearby permanent magnet. The induced poles are why the iron is attracted to the magnet. Induced polarization is always formed in the right direction to be attracted to, rather than repelled from, the magnet.

Likewise the induced polarization of the water puts mobile charges of opposite sign nearest to the external charge, and attraction naturally results.

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