Electrostatics

Earth's electric field

Feynman lectures: "There is a vertical electric field E of 100 volts/m in the air." 

http://www.feynmanlectures.caltech.edu/II_09.html

"This means that outdoors the potential at the height of your nose is 200 volts higher than the potential at your feet!" 

"You might wonder: “If there is really a potential difference of 200 volts between my nose and my feet, why is it I don’t get a shock when I go out into the street?”

Also: “Why don’t we just stick a pair of electrodes out in the air one meter apart and use the 100 volts to power our electric lights?”

Tapping into atmospheric electricity to generate power | https://youtu.be/2rVdEhyMR6A

In this video, a person lifts a wire to a point of 120 meters above the ground using a drone. That allows to generate a small amount of electricity which can make an electrostatic motor (corona motor) revolve. 

Under fair weather conditions, Earth's atmosphere contains a steady vertical electric field (E) of approximately 100 volts per meter (V/m), directed downward — from the positively charged ionosphere toward the negatively charged Earth's surface.

In other words, in the atmosphere, or more generally, in the air, the electric potential typically increases by about 100 volts per meter of altitude.

Earth’s surface is treated as having 0 volts, and each meter above it adds roughly 100 volts.

Excerpt from the video responding to the first question of the post: "But if this voltage exists between your head to the ground, why don't you get a shock? The reason is that your body is a good enough electrical conductor that standing on the ground you're basically a part of the ground. The equipotential lines would look like this (cf. figure of post)."

Figure 1: Electric gradient in the atmosphere (from https://youtu.be/2rVdEhyMR6A)

Electrostatic charging by friction and by induction

The following video illustrates the cases of being charged by friction and by induction:

https://www.youtube.com/watch?v=8Eiq1IMQyw8

1) A bee is charged by friction. This occurs as its flaps its wings very fast. The bee gets positively charged.

2) A pollen grain on a flower is charged by induction, initiated by the bee. This occurs because the positively charged bee induces a rearrangement of the charges of the grain, giving it a negative pole in proximity to the bee and a positive pole away from it. The later pulls electrons which ascend the host flower from the ground. (The flower "has earthing"). The pollen grain gets a surplus of electrons and becomes negatively charged. 

Bees bind pollen in this manner: the negatively charged pollen gets attached to the positively charged bee.

Experiments in electrostatics  from the Discovery Palace Museum (Paris)

We consider the metallic stage shown in Figure 1. Using an electrostatic generator, we charge it negatively up to the value of -350000 Volts. A person steps on the stage. Why do hair stand up?

First of all, for the stage to be charged negatively, electrons are deposited on it. It is considered that the generator deposits approximately 100000 billion electrons or ten to the 14th power for the stage to be charged at -350000 Volts.

The above number of electrons required to charge the stage at -350000 Volts is considered to represent an extremely low number. If one wants to use this quantity to power a pocket lamp (which uses a small battery), then the lamp would be on for a tiny fraction of a second. Powering it for one second requires a much bigger number of electrons.

https://youtu.be/seaCEEg_FGw?t=1983

The person that will step on the stage will be charged negatively as electrons will be deposited on him/her. As the entire body is being charged negatively, hair are also being charged negatively and are repelled by the negative head, while individual hairs also repel each other.

It is considered that 100 billion electrons are deposited on the person. The electrons and protons of the human body are ten to the 28th power.

https://www.youtube.com/watch?v=seaCEEg_FGw&t=2138s