Transcript Presentazione di PowerPoint

EXPERIMENTS AND PARADOXES
OF ELECTRICITY AND MAGNETISM
GUIDO PEGNA Dipartimento di Fisica
Università di Cagliari
[email protected] http://www.pegna.com
We present here some simple
apparatus and experiments
The goal is to stimulate curiosity,
the wish to understand,
the attitude to built self made
apparatus,
with the exercise of rationality
creative skills, good sense,
concreteness.
TO SEE THE VIDEOS PLEASE CLICK ON BLUE
“CLICK”
THE MISTERIOUS OSCILLATING
CIRCUIT CLICK
Rlc2_osc.wmv
The circuit
Why it oscillates at very low frequency?
100 € to whom who gives the solution!
(Write it to [email protected])
A series of two lamps and two switches
One switch lights one lamp
The other switch lights the second lamp
Both switches...both lamps
Where is the trick?
More
A lamp short circuited by a
thick copper conductor
copper tube
LOOK AT THIS PARADOX: CLICK
Is that a paradox?
What is contained in the base?
One more interesting
phenomenon
Levitation. A close-up view...
A small magnet levitates without
any external energy supply
What is this?
Magnet
And now:
a very interesting apparatus:
a completely static electrostatic
machine
Look at the following video...
THE COMPLETELY STATIC
ELECTROSTATIC MACHINE
high voltage terminal
Please note the effect on the
electroscope and on the electrostatic
motor without direct connections
in the following video
RUN! CLICK
One more interesting experiment
AN ELECTROMAGNETIC GUN CLICK
WITH AN OTHER PROJECTILE CLICK
A strange motor without
coils, brushes
N pole
magnet
+
contact
S pole
-
RUNNING ON A 1,5 V BATTERY CLICK
An extraordinary technological
exploit
The ultracapacitor: note the
value of the capacity

WHEN FULLY CHARGED THE ULTRACAP
MAKES THE MOTOR RUN FOR DAYS CLICK
A very clear demonstration of the
behaviour of inductors and capacitors
Lamp

Lamp

Lamp

Inductor
Capacitor
Resistor
Inverter
diagram
The lamps are connected in series
with the resistor, the inductor and
the capacitor and indicate the
current through those items
when the voltage is rapidly inverted
CURRENT THROUGH THE INDUCTOR CLICK
AND THROUGH THE CAPACITOR CLICK
CURRENT THROUGH BOTH INDUCTOR
AND CAPACITOR CLICK
A revolutionary table top apparatus
for the determination of the speed
of FREE propagating light
in 60 cm measuring base
Immediate set-up, nothig to aligne
Transmitter:
Laser modulated
at 450 MHz

Control
unit


Graduated
scale
Synchcronous
receiver sliding
on the guide


pointer
THE SPOT OF THE LASER CLICK
THE MEASURING POINTS ARE INDICATED BY
AN AUXILIARY AUDIO SIGNAL CLICK
Direct determination of the refraction index
in only 10 c.c. of a liquid
Tray

Scale
A small simple experiment
To demonstrate the thermoelectric effect
copper

Costantan
Coil

Compass
AND A GAS LIGHTER… CLICK
and many other intriguing
experiments
All these apparatus are original
creations of Prof. G. Pegna
of the Dipartimento di Fisica
Università di Cagliari, Sardinia, Italy.
Please take a look to many other
experiments and exhibits in:
http://www.pegna.com
Thank you!
CIENCIA EN ACCION
Cagliari, Italy, may 2011