phy electrostatics

1. The induced +ve charges are all on sphere X on the side near to the -ve charged rod, because of attractive force produced by the rod. There is no charge on sphere Y due to earthing of sphere X.

2. There are ions and electrons in the tap water that would neutralize the charges on the object.

3. In general, rubbing produces static charges. Hence, it could not be used for discharging. A charged conductor can be easily discharged just by touching it with a finger (i.e. earthing).

Whenever there is a charging or discharging process, there is electron transfer. Sharing alone cannot be used to discharge an object completely. Likewise, earthing alone cannot be used to charge an object.

4. Moisture is water vapour. There are ions and free electrons present in the vapour, which would neutralize the charges on the object.

2014-02-06 16:38:31 補充：
Your suppl question:
2. Either electrons in water adhere onto the charged body or electrons drawn from the charged body by +ve ions in water.

2014-02-06 16:42:14 補充：
3. What you described is, in fact, a "sharing charges by contact" process. You could neutralize the charges even without any rubbing.

2014-02-06 16:43:34 補充：
"Electron transfer" is a process, not a method. Any charging or discharging process involves "electron transfer"

2014-02-06 16:44:41 補充：
Just imagine, how could you "charge" a neutral object simply by connecting it to earth? Both of them are at the same potential.

2014-02-07 16:03:32 補充：
Your further question on (3):
Sharing of charge alone cannot be used to discharge a "charged object" COMPLETELY. After each "sharing", there bound to be some charges remain on the (originally) charged object.