Question

If you were wearing the sweater shown and rubbed your hand on it, you too would gain some negative charge on your hand. Then when you directly touch a metal conductor, like a doorknob, you will feel a shock. This is called conduction. From this scenario, where does the negative charge go when you touch a doorknob?

Answer 1

The negative charge from your hand moves to the metal doorknob, dispersing over its surface and neutralizing the excess charge, causing a static shock. A full-hand grip on metal objects in low-humidity areas is a strategy to distribute the induced charge and minimize the shock.

Step-by-step explanation:

When you rub your hand on a sweater and then touch a metal doorknob, you are demonstrating charging by conduction. The negative charge on your hand, due to excess electrons, transfers to the doorknob because like charges repel each other. These electrons distribute themselves on the outer surface of the doorknob, thereby reducing the negative charge on your hand and creating a spark or shock as the charge is dissipated.

In regions of low humidity, when touching metal objects, it is common to use a full hand grip to disperse the induced charge over a larger area, minimizing the shock experienced. This spread of charge reduces the concentration of excess electrons at any single point on the skin, leading to a less intense experience of the static discharge.

Overall, the negative charge acquired by your body as a result of friction with different materials is neutralized when you come in contact with a conductor, like a metal doorknob, resulting in familiar static shocks.