Energy Stored in Dielectric

• D+0+60

diagram for demo

Two metal buckets act as capacitor plates and a plastic inner bucket acts as a dielectric in the capacitor. The metal buckets are charged up with a Van de Graff generator. The inner metal bucket and dielectric are then carefully removed with an insulated rod to prevent any accidental electrical contact in between inner and outer bucket. Both metal buckets are discharged (the plastic dielectric can also be touched as it is an insulator). The system is reassembled and electrical contact is made in between the two metal buckets and a spark is produced. The spark is small so a camera can be used to illustrate the effect to the classroom. This occurs because the energy in the plastic dielectric is still present is sufficient quantity to recreate a charge difference in between the buckets.

Related Demos

D+0+1 Attraction between plates of a capacitor causes attachment of plates when insulator is introduced. D+0+0 Attraction between horizontal plates of a charged capacitor. D+0+2 Various capacitors to show. D+0+4 Parallel plate capacitor with dielectric materials and electroscope. D+0+6 Capacitor doorbell driven by Van de Graaff generator. D+0+8 Series capacitor array. D+0+10 Parallel capacitors array: A charged capacitor charges the others. D+0+12 Visual charge/discharge of a capacitor through a load. D+0+14 Computer demo: Charge/discharge of a capacitor, runs at least 1 min. D+0+16 Discharging a capacitor through a lamp. D+0+18 Capacitors with a series neon bulb on A.C. and D.C. D+0+20 Capacitor in series in an audio circuit: High pass filter. D+0+22 Effects of changing a D.C. voltage in a series RC circuit. D+0+24 Capacitor in parallel in an audio circuit: Low pass filter. D+0+26 Capacitor in parallel in a D.C. circuit. D+0+28 Energy storage in a commercial capacitor. Loud bang! D+0+30 Oscillator made with resistor, capacitor and neon lamp. D+0+32 Same as D+0+30 using speaker for audio tone generation. D+0+34 Same as D+0+30 using oscilloscope to display waveform. D+0+5 Force on a dielectric in a capacitor D+0+35 Applet: Capacitor Lab D+0+40 Applet: Circuit Construction Kit (AC+DC), Virtual Lab D+0+45 Applet: Water Droplets in Electric Field D+0+50 Applet: RC Circuits D+0+55 Applet: CR Filter's Response (Analog)