Neon Bulb – Make it Glow!
Using static electricity to generate flashes of light
Topics: Static electricity
Materials List
 Neon lamp (NE-2),
commonly called a
neon bulb
 Paperclips, 2, #1
(small size, not
jumbo)
 Black film can or
portion cup
 Single hole punch
 Way to generate
charge separations
(static charges)
This activity can be used
to teach:
 Energy can be
transferred from place
to place and
converted from one
form to another (Next
Generation Science
Standards, Grade 4,
Physical Science 3-2
& 3-4; High School,
Physical Science 3-3)
 Electric or magnetic
interactions between
objects not in contact
with each other (Next
Generation Science
Standards: Middle
School, Physical
Science 2-5; High
School, Physical
Science 3-2, 3-5)
Static electricity can light up a neon bulb, no batteries needed! Handling the bulb and
observing the flashes are made easier by mounting the bulb in a black container.
Assembly
1. Use a single-hole punch to make a hole in the side of a black film can or portion
cup. Make the hole about halfway down the side.
2. Attach 2 paperclips on either side of the hole, angling away from the hole.
3. Bend the neon bulb’s leads at right angles to the bulb.
4. Insert the bulb into the hole in the film can or portion cup and slip the wire leads
under the paperclip loops that are on the outside, one to each paperclip. Wrap
each lead around and through the paperclip loop to secure the end in place.
To Do and Notice
Note - results will vary with temperature and, especially, humidity!
1. Hold the film can so that no fingers touch either paperclip.
2. Bring a charged surface near to one paperclip. Does the bulb flash?
3. Repeat step 2 but touch the opposite paperclip with a finger.
4. Repeat step 2 but bring a charged electrophorus near one paperclip (see idea sheet
Electrophorus – a Charge Carrier). Is the glow brighter?
The Science Behind the Activity
Neon bulbs (lamps) generate light when electrons leave an electrode and strike the
atoms of neon gas (other gases can be used). This excites the electrons in the gas,
making them move to higher energy levels (orbits). Light (orange for neon gas) is
given off when the excited electrons drop “down” to their normal energy levels. This
process requires about 80 volts but very little current (electron flow). The flash will
be greater if the charge separation and/or amount of available electrons is greater.
Electrons can move much more easily and rapidly in a conductor such as the metal
paperclips. An electrophorus, having a metal surface, will supply more electrons
generating a brighter flash of light.
Taking it Further
A neon bulb can be used to determine the sign of a charge, and thus, the direction of
electrons’ motion! Identifying the direction of electron flow requires very careful
observation of the position of the neon glow. This glow will surround only the
negative electrode. Blocking the very bright center glow between the electrodes can
make the fainter side glow more noticeable.
Electrons will move away from the negative electrode, towards the positive electrode.
The negative charge, a cloud of electrons, will be near, or touching, the lead of the
electrode that is surrounded by the glow. A finger can take on or give off electrons to
match the negative or positive charge that is lighting up the neon bulb.
A static charge might cause the feeling of a “static shock”.
Web Resources (Visit www.raft.net/raft-idea?isid=241 for more resources!)
http://www.exo.net/~pauld/summer_institute/summer_day15current/Neontubes.html
Designed and written by Michael Pollock (RAFT)
Copyright 2015, RAFT