Conductors, Capacitors, Dielectrics

Electrostatics with Conductors

Video RealVideo®
9:20 minutes (41:41 - 51:01)

Explanation of how a Van de Graaff generator works, with a demonstration of making one manually.

Instructor: Prof. Walter Lewin
Prior Knowledge: None
Back to Top
Video RealVideo®
6:29 minutes (25:21 - 31:50)

Charge placed on a hollow conductor will be distributed only on the outside surface. Demonstration using a metal paint can that there is no electric field inside a charged hollow conductor. Electric shielding is defined.

Instructor: Prof. Walter Lewin
Prior Knowledge: Conductors (7:15 of VL1, 20:33 of VL5)
Back to Top
Video RealVideo®
6:46 minutes (43:12 - 49:58)

Using a paint can to show that a hollow conductor in an electric field has charge distributed on the outside but no charge on the inside surface. Bringing a radio into a giant Faraday cage to demonstrate electric shielding. Getting inside a charged Faraday cage to show there is no charge on the inside surface.

Instructor: Prof. Walter Lewin
Prior Knowledge: Conductors (7:15 of VL1, 20:33 of VL5)
Back to Top
Video RealVideo®
2:36 minutes (6:29 - 9:05)

Charging up a metal cooking pot to show that there is higher charge density where the curvature is greater on a conductor.

Instructor: Prof. Walter Lewin
Prior Knowledge: Conductors (7:15 of VL1, 20:33 of VL5)
Back to Top
Video RealVideo®
11:51 minutes (35:27 - 47:18)

Repositioning the components of the Kelvin Water Dropper to demonstrate other interesting behavior.

Instructor: Prof. Walter Lewin
Prior Knowledge: Kelvin Water Dropper (44:02 of VL10)
Back to Top
Video RealVideo®
5:35 minutes (40:25 - 46:00)

Creating sparks and corona discharge by holding a conducting sphere, a conducting point, and tinsel near the Van de Graaff generator.

Instructor: Prof. Walter Lewin
Prior Knowledge: Sparks (9:05 of VL6)
Back to Top
Video RealVideo®
6:35 minutes (46:00 - 52:35)

How corona discharge may have caused the Hindenburg disaster. How Napoleon used a gun to test for marsh gas in Egypt, with a demonstration.

Instructor: Prof. Walter Lewin
Prior Knowledge: Sparks (9:05 of VL6)
Back to Top

Capacitance

Video RealVideo®
2:52 minutes (30:20 - 33:12)

Starting to charge a large capacitor to a potential difference of 3000V.

Instructor: Prof. Walter Lewin
Prior Knowledge: Capacitance (10:07 of VL7)
Back to Top
Video RealVideo®
4:48 minutes (33:12 - 38:00)

Explanation of the concepts behind a camera flash, with a demonstration using several capacitors and a light bulb.

Instructor: Prof. Walter Lewin
Prior Knowledge: Capacitance (10:07 of VL7)
Back to Top
Video RealVideo®
3:59 minutes (45:27 - 49:26)

After 15 minutes of charging, the capacitor is quickly discharged over a fuse with impressive results.

Instructor: Prof. Walter Lewin
Prior Knowledge: Capacitance (10:07 of VL7) and Charging a Large Capacitor (30:20 of VL7)
Back to Top

Parallel Plate

Video RealVideo®
6:21 minutes (23:59 - 30:20)

Using an actual parallel plate capacitor to show that positive work must be done to increase the distance between the two plates.

Instructor: Prof. Walter Lewin
Prior Knowledge: Capacitance (10:07 of VL7)
Back to Top
Video RealVideo®
5:06 minutes (11:34 - 16:40)

The effects of increasing the separation between the plates of a capacitor.

Instructor: Prof. Walter Lewin
Prior Knowledge: Capacitance (10:07 of VL7)
Back to Top
Video RealVideo®
7:48 minutes (18:53 - 26:41)

The effects of increasing the separation between the plates of a capacitor that is still connected to a power supply.

Instructor: Prof. Walter Lewin
Prior Knowledge: Capacitance (10:07 of VL7)
Back to Top
Video RealVideo®
5:33 minutes (36:08 - 41:41)

Definition and demonstration of a Leyden Jar.

Instructor: Prof. Walter Lewin
Prior Knowledge: Capacitance (10:07 of VL7) and Dielectrics (Beginning of VL8)
Back to Top
Video RealVideo®
17:26 minutes (32:58 - 50:24)

Demonstration of the Leyden Jar, with explanation of the physics behind the unexpected result.

Instructor: Prof. Walter Lewin
Prior Knowledge: Leyden Jar (36:08 of VL8)
Back to Top

Dielectrics

Video RealVideo®
2:13 minutes (16:40 - 18:53)

The effects of inserting a dielectric between the plates of a capacitor.

Instructor: Prof. Walter Lewin
Prior Knowledge: Dielectrics (Beginning of VL8)
Back to Top
Video RealVideo®
4:24 minutes (26:41 - 31:05)

The effects of inserting a dielectric between the plates of a capacitor that is still connected to a power supply.

Instructor: Prof. Walter Lewin
Prior Knowledge: Dielectrics (Beginning of VL8)
Back to Top
Video RealVideo®
5:33 minutes (36:08 - 41:41)

Definition and demonstration of a Leyden Jar.

Instructor: Prof. Walter Lewin
Prior Knowledge: Capacitance (10:07 of VL7) and Dielectrics (Beginning of VL8)
Back to Top
Video RealVideo®
17:26 minutes (32:58 - 50:24)

Demonstration of the Leyden Jar, with explanation of the physics behind the unexpected result.

Instructor: Prof. Walter Lewin
Prior Knowledge: Leyden Jar (36:08 of VL8)
Back to Top