Message-Id: <v01540b15b16bbd50a77f@[192.174.2.173]>
Date: Tue, 28 Apr 1998 09:17:51 -0800
To: pinhole@exploratorium.edu
From: pauld@exploratorium.edu (Paul Doherty)
Subject: Re: electrostatic saturday
Hi Neil
Where does charge come from when two objects are rubbed together?
It is a great question because scientists are just now finding the answer
using scanning tunneling microscopy.
In a recent experiment a nickel point was touched to a gold surface. After
the touch, several gold atoms were transferred to the nickel. This shows
that during intimate contact, such as rubbing, entire clusters of atoms can
be transferred from one material to another. These atom clusters need not
be neutral, the two different materials almost certainly have different
attractions for electrons. This means that the clusters of atoms that are
transferred can be positive or negative.
An entire series called the triboelectric series has been assembled, which
tells which materials become positive and which become negative when they
are rubbed together.
TRIBOELECTRIC SERIES
Human Hands <---- Most Positive
Asbestos
Rabbit Fur
Glass
Mica
Human Hair
Nylon
Wool
Fur
Lead
Silk
Aluminum
Paper
Cotton ZERO
Steel
Wood
Amber
Sealing Wax
Hard Rubber
Nickel, Copper
Brass, Silver
Gold, Platinum most negative