# Franck-Hertz experiment is not quantized

Discussion in 'Electronic Basics' started by [email protected], Oct 12, 2005.

1. ### Guest

16 Franck-Hertz experiment is not quantized
Ed 01.12.31 ----------------------------------------
Abstract
--------
By increasing the voltage in the Franck-Hertz experiment we reach a
breakdown voltage in which the current existent between the grid and
anode is canceled. This breakdown voltage will be repeated at equal
intervals by increasing the voltage.

I. Introduction
---------------
As an evidence that even absorption of kinetic energy by an atom is
quantized the Franck-Hertz experiment is cited. It is said that this
experiment shows clearly that the kinetic energy of an electron
colliding
with an atom will be absorbed by the atom only when it is exactly equal
to the distance between the energy levels of the electron in the atom.
In other words, only when it has some definite amounts it'll be
absorbed
this experiment is not really a quantum process but a simple mechanical
and electric one rather similar to when you are trying to separate the
apples of an apple tree by shaking its trunk. When your energy exerted
on the trunk is not sufficient (equal to a definite amount) no apple
will fall, but when it is the case, suddenly many apples will fall.

II. Analysis of the Franck-Hertz experiment
-------------------------------------------
In the Franck-Hertz experiment, as shown in Fig. 1, the grid G is
located
near the Anode A while the high potential difference V between G and
the
cathode C is variable but the low potential difference between A and G
is
constant.

|-----------------------------------------|
| C G |
^^^^^^^^\ | : A |
| | | : | |
| | | : |-------|
| | | : | | |
_______/ | : | / \
|-----|------------------------------|----| ( I )
| /^\ | \ /
|---------( V )----------------| V' |
| \_/ | | | |
|---------------| ... |--------|--||-----|
| a |
- + +-
Fig. 1.

The gas under experiment is in the lamp containing C, G and A. When C
is
warmed up (electrically), the experiment starts. Variation of I, the
current of A, with V is something like what is shown in Fig. 2 in which
the horizontal distance between each two adjacent tops is the same.

/^\
|
|
|
I | .'` .'` .'` .'`
| . | . | . | . |
| _-` ' _-` ' _-` ' _-` '
| .- ` .- ` .- ` .- `
|/` ,/` ,/` ,/`
---|---------------------------------------------------------->
| V

Fig. 2.

The curve falls abruptly after each top (not quite normally but with a

As I have explained in Articles 9 and 12 and 1st appendix of the book,
electric current is a continuous process, in which an electron train is
moving (ie as if the electrons, taking part in the current, are in
touch
with each other in a train of themselves each exerting force on the
next),
not a colliding one. Let's remove the grid G temporarily. In this
state,
when the cathode C has not yet been warmed no current flows in the
circuit.
But when as a stimulation C is warmed, a current of electrons will flow
in the circuit in the direction from C to A. Why? Because, the constant
voltage V' is smaller than V and then the situation is as if the source
of potential in the circuit is a single battery which its negative pole
is connected to C and its positive pole is connected to A. Thus,
certainly
we shall have an electron current from C to A when the cathode is
warmed.
In this state let's restore G. Certainly, now, only a part of the
current
will flow via the grid toward the point a, and the rest of it still
flows
toward A (through the holes in the grid).

Now let's consider the right circuit consisting of G, A and V' before
warming the cathode up, ie before causing any current to flow in the
circuit. In this state, what can cause an electron current to flow in
this (sub)circuit from A to G? Just the same factor that causes an
electron current in the main circuit from C to A, ie (the stimulation
caused by) heat. But we have not given any external (electric) heat to
the
space between A and G as done in the main circuit when warming C up.
That's right, but such a heat can be provided by the electric current
flowed in the space between G and A. Such a heat should be sufficient
if it is to cause freedom of the electrons of the atoms of the gas from
these atoms and an electron current in the right (sub)circuit from A to
G, otherwise there won't be such a current even though the space
between G and A is warmed (insufficiently).

Thus, if the total current in the circuit, from C to G, is sufficiently
intense (which this occurs when V is sufficiently high), sufficient
heat,
due to passing of the electron current from G to A, will be produced to
cause freedom of the electrons of the atoms ie stimulation of the right
circuit to cause an electron current to flow from A to G. But this
recent
electron current from A to G will cancel the main electron current in
the
main circuit from G to A, and the result is that there will be no
current
practically. When there is no current in the space between G and A,
there won't be any heat produced due to it, and then there
won't be any stimulation to cause any electron current (in the right
circuit) to flow from A to G, and then the story can be repeated, ie by
increasing the voltage V, the electron current is again increased until
when the heat produced due to it stimulates the voltage V' to cause an
equal but opositely directed electron current to flow causing a renewed
fall in the curve of I against V just at a point as far from the
previous
point of fall as the next point of fall.

Of course, in the real curves, each (new) peak is (a little)
higher than the previous one. What presented above excluded
this aspect of the experiment as an unimportant thing for the general
justification of the main result of the experiment (ie existence of
repeated falls in the curve at equal distances).
What can be said at present for the probable cause of this effect is
that by increasing the voltage there may be some electrons flowing from
Cathode to Anode due to field emission. These electrons themselves make
a ground current having no relation to the current produced by
displacing
of the valence electrons of the atoms of the gas in the tube. Only this
recent current (ie one due to displacing of the valence electrons of
the
gas atoms) can give heat to the atoms (causing separation of their
electrons if this heat is sufficiently big), because the electrons of
only this current are in direct contact with the atoms. This suggestion
can probably be tested by study on any alteration in the results of the
experiment when we try to eliminate as many causes for the field
emission as possible.

Hamid V. Ansari

The contents of the book "Great mistakes of the physicists":

0 Physics without Modern Physics
1 Geomagnetic field reason
2 Compton effect is a Doppler effect
3 Deviation of light by Sun is optical
4 Stellar aberration with ether drag
5 Stern-Gerlach experiment is not quantized
6 Electrostatics mistakes; Capacitance independence from dielectric
7 Surface tension theory; Glaring mistakes
8 Logical justification of the Hall effect
9 Actuality of the electric current
10 Photoelectric effect is not quantized
11 Wrong construing of the Boltzmann factor; E=h<nu> is wrong
12 Wavy behavior of electron beams is classical
13 Electromagnetic theory without relativity
14 Cylindrical wave, wave equation, and mistakes
15 Definitions of mass and force; A critique
16 Franck-Hertz experiment is not quantized
17 A wave-based polishing theory
18 What the electric conductor is
19 Why torque on stationary bodies is zero
A1 Solution to four-color problem
A2 A proof for Goldbach's conjecture

2. ### Michael A. TerrellGuest

--
?

Michael A. Terrell
Central Florida

3. ### The Ghost In The MachineGuest

In sci.physics, Michael A. Terrell
<>
wrote

"The"? ;-) We've a few here in sci.physics; I can't say regarding

You're welcome to borrow one or two of 'em, of course...just make
sure to return them in good condition.

4. ### Uncle AlGuest

[snip crap]

Idiot.
Never trust an idiot who cannot count beyond fingers and toes.

5. ### Michael A. TerrellGuest

If I can't use them for target practice, I don't want them.

I found an old set of lawn darts the other day, I wonder which is
harder, their skulls, ot the steel tips? ;-)

BTW, there is a real one on . If you
ignore him, he will call you and make threats.

6. ### HarryGuest

At first sight that look like Trichel pulses. Who claims that this is a
quantum effect, and where?

Thanks,
Harald

7. ### Kitchen ManGuest

Or starts a numbered list with zero.

8. ### Kevin AylwardGuest

I do, as does anyone that knows 101 physics.

http://hyperphysics.phy-astr.gsu.edu/hbase/FrHz.html

Kevin Aylward

http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.

9. ### Rich, Under the AffluenceGuest

Presumably, the dart. They've been banned in the US for some time now.

And bullets are definitely harder than the skull, even of innocent
bystanders - every year, about cinco de Mayo in So Cal, there are
news reports of kids killed by bullets fired into the air by idiots.

Good Luck!
Rich

10. ### Jasen BettsGuest

why do you suppose the electron current then flows to?

This does not explain why the current measured is in the opposite direction
to that which would normally be caused by the battery (V').

It seems to me that if your hypothesis were to be true then the gas pressure
would effect the spacing between the peaks, have you observed that ? and if
not why not?

Bye.
Jasen

11. ### Guest

"The values of accelerating voltage where the current dropped gave a
measure of the energy necessary to force an electron to an excited
state."

OK, trichel pulses may be called a "quantum effect" if one calls
electron emission a quantum effect (I consider the particle behaviour
of atoms and electrons to be "classical"). Anyway, I didn't get the
impression that that was the issue.

Cheers,
Harald

12. ### harryGuest

OK it wasn't what it looked to me, this is much clearer.

"The values of accelerating voltage where the current dropped gave a
measure of the energy necessary to force an electron to an excited
state."

Harald

13. ### Kevin AylwardGuest

Ahmmm...

The fact that atoms absorb and emit energy by electronics moving to
different "orbits" in *discrete* steps is one of the fundamental corner
stones of QM. The spectrum of the hydrogen atom was only explained by
such quantisation.

Kevin Aylward

http://www.anasoft.co.uk
SuperSpice, a very affordable Mixed-Mode
Windows Simulator with Schematic Capture,
Waveform Display, FFT's and Filter Design.

14. ### HarryGuest

Yes I agree, the ASCII plot looked like Trichel pulses but it wasn't that at
all.

Cheers,
Harald