5E40.24/4F30.15 Fuel Cell
Electricity & Magnetism Demonstrations
Demonstration Manager: Gerald Zani
Thousands of volts discharge between conducting spheres
Producing Static Charge  
To demonstrate electric charge .  5A10.10  
To produce small amounts of negative or positive static electric charge.  5A10.21  
To show that the total amount of charge is conserved when charges are separated by friction.  5A10.35  
Coulomb's Law 



To demonstrate the separation of electric charge.  5A20.10  
To show electric charge.  5A20.20  
To show coulomb repulsion.  5A20.30  
Electrostatic Meters 


To measure electric charge.  5A22.10  
To show electric charge.  5A22.30  
To measure the small voltages or small currents due to electric charges.  5A22.71  
To show electric charge.  5A22.72  
To show electric charge.  5A22.80  
Conductors and Insulators  
To show that a neutral, uncharged conductor is attracted by both positive and negative charge.  5A30.16  
To show that glass is an insulator when cold, but when heated the resistance changes and it becomes a conductor.  5A30.20  
Induced Charge 


To illustrate charging by induction.  5A40.10  
To show induced polarization of charge  5A40.22  
To show induced dipole attraction and repulsion.  5A40.24  
To demonstrate polarization of water molecules.  5A40.30 Name is Different on Page  
Electrostatic Machines 


To generate high electrostatic potentials.  5A50.10  
To demonstrate operation of Van de Graaf and illustrate electrostatic concepts.  5A50.30  
Electric Field 


To show electric charge repulsion.  5B10.10  
A foam packing peanut between two charged plates represents a point charge in an electric field.  5B10.25  
A conductive pith ball bounces back and forth in the electric field between two charged plates.  5B10.30  
Show electric field lines for five different charge distributions.  5B10.40  
A large model for the torque induced on an electric dipole in a uniform electric field.  5B10.50  
Gauss's Law 


To show the location of charge on a conductor.  5B20.10  
To show that the charge deposited inside a conductor resides on the outside surface, and the charge inside is zero.  5B20.15  
To show the shielding effect of a Faraday Cage.  5B20.35  
To show that the electric field inside a conductor is zero.  5B20.36  
Electrostatic Potential 


To show the different surface charge densities of the pointed end versus the blunt end of a charged, conducting zeppelin.  5B30.20  
To demonstrate that for conductors at the same electric potential the rate of discharge of the electric field is HIGHER for a conductor with a SMALLER radius.  5B30.35  
Capacitors 


To compare a variety of capacitor flavors and colors.  5C10.10  
To show that if the amount of charge is constant, then changing the distance between the plates of a capacitor will also change the capacitance and the voltage, Q=CV.  5C10.20  
To demonstrate that an isolated plate of a capacitor becomes saturated easily with charge and can build up a potential but when a second grounded plate is brought nearby, the potential for that charge is reduced and now you can add a lot more charge to the same plate.  5C10.22  
Dielectrics 


Demonstrate the force on a dielectric in an electric field.  5C20.20  
To model the torque caused by the force of an external electric field acting on an electric dipole moment.  5C20.33  
The magnetic field generated by a displacement current is measured in between two plates of a capacitor.  5C20.60 Photo  
Energy Stored in a Capacitor 


To show the quick release of the energy stored in a large capacitor.  5C30.20  
To show the mechanical equivalent of the electric energy stored in a capacitor, and to show that this amount of energy is proportional to the square of the voltage.  5C30.30 Photo  
A large capacitor is discharged after being charged first in series then in parallel with a small capacitor to show the difference in the energy stored in both cases.  5C30.40  
Resistance Characteristics  
To show the relationship between resistance and area using carbon paper.  5D10.15  
To show the resistances of different pencil line circuits.  5D10.49  
Resistivity and Temperature 


To show zero resistance.  5D20.55  
To show that the resistance of glass is lower at higher temperature.  5D20.60 Duplicate Name  
To show that the resistance changes with the temperature.  5E20.10  
Cells and Batteries 


This is a demo of fuel cell technology.  5E40.24  
Creation of a primitive battery using pieces of zinc and copper embedded in a citrus fruit.  5E40.25  
Peltier and Seebeck effect demonstrated through a single bismuthtelluride thermoelectric couple.  5E50.60  
Ohm's Law 


To show the resistance of a wire is proportional to length, and to show how the power to a lamp is decreased when the resistance of the wire is increased.  5F10.20  
Circuit Analysis 


To illustrate the motion of electrons in a circuit.  5F20.15  
To demonstrate Kirkoff's laws with a series and a parallel connection of two identical light bulbs.  5F20.49  
A simple circuits to encourage thought about the relationships between resistance, current, voltage and power.  5F20.50  
RC Circuits 


To show the voltage curve when a capacitor is charged.  5F30.20  
To show the difference between the potential across the resistor over time and the potential across the capacitor over time.  5F30.23  
To show the time constant of an RC circuit.  5F30.24  
To show the RC time constant.  5F30.60  
Magnets 


To demonstrate the magnetism of a natural lodestone.  5G10.10  
To introduce the idea that the magnetic force can penetrate your hand (a nonferrous material) without apparent obstruction.  5G10.11  
To show that splitting a magnet in half does not yield two monopoles.  5G10.20  
Magnet Domains 


To show the polarization of ferromagnetic domains in a material.  5G20.20  
To show the strength of the magnetic field produced by running current through a coil.  5G20.70  
Paramagnetism and Diamagnetism 


To show paramagnetic materials are attracted to magnetic fields.  5G30.20  
To show diamagnetic levitation  5G30.45  
Temperature and Magnetism 


To the curie point of Nickel.  5G50.10  
To show the Meissner effect.  5G50.50  
Fields and Currents 


To show the dip angle of the Earth's magnetic field.  5H10.15  
To visualize the magnetic field of a bar magnet.  5H10.30  
To demonstrate magnetic shielding.  5H10.61 Photo  
To show that a magnetic field is created by a current wire.  5H15.10  
To show the magnetic field of a solenoid.  5H15.40  
To show the field inside, outside, and at the ends of a long solenoid.  5H15.47  
To show the field of a toroid.  5H15.50  
When current runs through a solenoid, a uniform magnetic field is induced inside the solenoid  5H15.70  
Forces on Magnets 


To show the force one magnet exerts on another.  5H20.10  
A spinning magnet levitates over a toroidal magnet.  5H20.22  
Magnet and Electromagnet 


To show that the an electromagnet has a field that is similar to a bar magnet.  5H25.10  
To show that the an electromagnet is similar to a bar magnet.  5H25.11  
Force on a Moving Charge 


To demonstrate the force on an electron beam by a magnetic field from a magnet.  5H30.10  
To demonstrate the force on an electron beam by a magnetic field from a pair of Helmholtz coils.  5H30.15  
Force on a Current 


To show that the current in a wire will create a magnetic field.  5H40.10  
To demonstrate the force on a currentcarrying wire in a magnetic field.  5H40.30  
To show the relationship between the angle of the magnetic field relative to a current carrying wire and the force on the wire.  5H40.36  
To demonstrate how an electric potential difference and a current can be generated when a conductor moves through a magnetic field.  5H40.60  
Torque on a Current Loop 


Torque on a Loop  To demonstrate that a magnetic field exerts a net torque on a current loop.  5H50.20 
To show that the forces on a current loop inserted in a magnetic field are determined by the direction of the current.  5H50.30  
Self Inductance 


To demonstrate the back EMF caused by interrupting the current of a coil.  5J10.23  
LR Circuits 


To show the rise time of the current through the resistor in an RL circuit.  5J20.10  
To show self inductance and back EMF.  5J20.20  
To show the change in brightness of two bulbs, one in series and one in parallel with an inductor, when a switch is opened and closed.  5J20.22  
To show the difference between voltage across the inductor over time and the voltage across the resistor over time.  5J20.30  
RLC Circuits (DC) 


To show the ringing from an RLC circuit.  5J30.10  
Induced Currents 


To show rotating a coil in a magnetic field induces a current.  5K10.10  
To show that a current is induced in a coil by a changing magnet field.  5K10.20  
To demonstrate generation of DC voltage with the rotational motion of a magnet and a conductor using a method which may involve an explanation other than electromagnetic induction. This demonstration is also known as the "Motional EMF Demonstration", the "Homopolar Generator" and the "Unipolar Motor".  5K10.80  
To crush an aluminum can with a strong field strength, specifically an electromagnetic field.  5K10.90  
Eddy Currents 


To show the braking effects of induced eddy currents.  5K20.10  
To show Lenz's Law in a dramatic way.  5K20.25  
To show some concepts about magnetic induction.  5K20.30  
To show that a magnet on a pivot held above a spinning disk will rotate.  5K20.42  
Transformers 


To show a step up transformer.  5K30.50  
Currently Unavailable.  5K30.51  
Motors and Generators 


To show how a DC motor works.  5K40.10  
To show how mechanical energy can be converted into electrical energy.  5K40.81  
To demonstrate a how a person can pedal a simple DC generator and transform mechanical energy into electrical energy capable of delivering up to a kilowatt of power directly to a resistive load.  5K40.83  
Impedance 


To show the L/R time constant of an inductive circuit and that the voltage leads the current by 90 degrees.  5L10.20  
RLC Circuits (AC) 


To demonstrate resonance in an LC circuit.  5L20.10  
AC Filters and Rectifiers  
To compare the voltages for AC and DC current necessary to produce the same power.  5L30.25  
Semiconductors 


To show the hall effect.  5M10.10 Photo  
To show a PN photocell.  5M10.60  
To show a silicon semiconductor.  5M10.63  
Tubes 


To show a vacuum tube.  5M20.33  
Transmission Lines and Antennas 


To show a large coaxial cable transmission line.  5N10.10  
To show the polarization of microwaves.  5N10.16  
To demonstrate microwave standing waves.  5N10.55  
Light Bulb in a Microwave  To demonstrate the electromagnetic fields are waves with a speed and wavelength that carry energy.  5N10.58 
To demonstrate that energy is transmitted through space in the form of electromagnetic waves, and also to show the waves are polarized.  5N10.60  
5N10.70  
Tesla Coil 


To demonstrate a Tesla coil and show how magnetic induction and resonance is used in the production of highvoltage and the wireless transmission of electricity.  5N20.40  
Electromagnetic Spectrum 


To show the spectrum of white light.  5N30.10 