Transcript of Julius Sumner Miller: Lesson 39 - Adventures with Electric Charges

ch [Music] how do you do ladies and gentlemen and teachers and boys and girls and mothers and fathers and people I'm Julia Suna Miller and physics is my business and our special business today adventures with electric Chargers Adventures some wonderful things really consider the following here is a slab of lose site I've now handled it abundantly it is electrostatically neutral here is a metal plate on an insulating handle it is electrostatically neutral I lay the plate on the slab and I lift it and all I'm lifting is the weight of the plate now I'm going to do something I'm going to do some work on this slab of loose sight I am slapping it with a fur I have endowed that slab with some strange electric properties proof I'm going to put the metal plate on the slab and I'm going to put my finger on the upper surface of the metal plate and then I'm going to lift the plate with ever so great a delicacy uh correction a delicateness oh it's very heavy there are some electrostatic binding forces kolon forces we call them and I'll show you that I have some electric energy in this metal plate or on it listen now ha there was a discharge there is a discharge there is a discharge and I continue I can continue to take electric energy from this system forever forever which is a very long time indeed the electric energy available to me there could light a fluorescent lamp which it may be difficult to see but that's all right I assert it will excite or light the lamp yes yes I saw it it's a little difficult in the studio with these much lights here is a tube called a spectrum tube it is uh it contains some Neon gas and it takes about 5,000 volt FSE to excite this tube I'm going to show you that I can Flash that tube watch it there it is it flashed it flashed so the electrophorus that's what that is called an electrophorus first put together by the wonderful alesandro Volta in Italy called Italy now some more on these matters adventures with electric Chargers I have here a vyra generator and here I have a a tube in which I'm going to put some cigarette smoke getting most of it in my eyes that tube is filled with cigarette smoke I'm going to connect that tube to this vagra generator which can supply me with a large difference of potential watch the smoke watch the smoke will you just connect the generator for me please a moment there you see it thank you very much there was a precipitation ation of the smoke in this flask in this tube which suggests that the smoke was possessed of made up of charge particles now I'm going to discharge that vandag graph because uh it could be a little risky for me let me show you something more wonderful still here is a three-pointed vehicle like a lawn sprinkler notice the arms are bent at right angles to themselves and sharply pointed I'm going to put this on the vagra the system is at rest and we will in a moment energize the vagra and you will see an astonishing thing we hope that little uh uh spin wheel thing will turn watch it let me have it please there it is there it is turning thank you sir notice there was not much charge on this sphere of the vandra generator not why because Shar points are good lightning arrestors or they speedily discharge the charge gathered which tells us why lightning arresters are sharply pointed consider this which I call the Mad professor's head some Bits of Paper I'm going to make connection with the vandag graph every little sliver will acquire the same charge and what should they do watch it now just a minute hold on will you please energize that machine for me look at here look at that and notice too thank you sir notice down there the field is so strong as to be felt at a distance let me have that once more cuz I like it there it is I think that's wonderful thank you I'm going to try it once more hold on hold on I'm going to present my own head there and I hope you will see the hair stand on end a little please oh yes I feel it that's enough notice we nearly had a disaster cuz I felt a discharge one more matter here I have notice how caution I am here I have a candle flame and nearby it a sharp pointed rod and nearby it on this side a spherical conductor and I hope you see those very clearly and I'm going to suggest the following here is the flame of the candle there is the flame of the candle thermal energy gives rise to ionization there are then in this flame produced by the flame some positive ions and some negative ions if I have the sharp point of a conductor which is connected with a vandag graph supposing there is an abundance of positive charges here and this vandag graph is negative do you see what's going to happen the flame will be dragged over on the other hand if we uh change the charge on one of these the flame will be pushed away I'm going to connect to the vandag graph and watch now wait wait I have to make connection I have to make connection here I'm making connection with the with the rod near the flame if you will energize that please watch it oh we had a little trouble thank you I had a feeling that the flame was pushed away but we're in a little mechanical trouble which need not fret us too much now consider the following incredible device a laden jar dissectable meaning I can take it apart metal insulator metal conductor I am going to charge it on the vandag graph storing some electric energy in this vessel if you will please enough I'm going to show you that there's some electric energy there watch now what happens when I connect the outermost and the innermost watch it oh and there's always some more there it is and always some more so we have found evidence of storing some electric charge in that vessel called a laden jar l e y d n Laden or Leiden after Holland Peter Von mushen Brook discovered this indeed he had a shock which so stirred him that he said he would not take such another for the whole Kingdom of France now I want to show you something very remarkable about this vessel going to charge it again please enough now I am going to disassemble it there it is I have disassembled it and connected all the parts would you not think that I have discharged the instrument after all I connected the outermost and the innermost watch me now I now assemble it and now watch watch oh ho that's a killer that's a killer I remember when I first saw this 50 years ago it puzzled me nearly to to Madness because I didn't understand it and so I suggest that those students who understand this they deserve an A in this subject of electrostatics I'm going to do that that again so you'll see that there's no fluke again if you please thank you notice notice the greater the charge on the sphere the greater the charge on this and I feel the hair on my arm standing on in and pretty soon I might have it so watch I'm going to disassemble it I'm going to disassemble it notice with absolute abandon no absolute abandon assemble it outermost inner innermost watch it now watch it ah the energy is still there and I want to know how it is that Rascal works now I have another one a bigger one this is a glass vessel which is coated on the inside with a metal uh foil so it's a conductor inside it is coated on the outside with a metal foil so it's just like that d desable Len jar that I had a moment ago but this one cannot be dissected parenthetically you notice I pronounce the word disected not dissected it is not dissection when you cut up fishes and mollusks and cats and things the word is dissect uh and the word is also bisect but not dissect watch me I'm going to store some electric energy in this if you will please hold it hold it hold it now if you will please I would say that's enough thank you and I think there's enough electric energy in here to knock down a horse watch I'm going to connect the innermost and the outermost watch watch watch oh mother that is incredible that is something I would say that could knock me down once more cuz I I it's very dramatic once more oh hold it Nelly I feel the hair on my arm standing on end I feel my eyebrows beginning to tickle which means that I'm getting loaded with electric charge and now watch the energy in this system incredible watch it now watch it oh as we say a be I'm going to be sure a capacitor a laden jar uh discharges exponentially which means there's always some there and one should never take a risk with it do you understand why it was that Peter Von mhre playing with these things in the 17th century said having taken a shot that he would not take such another for the kingdom of France so we have explored some wonderful adventures in electrostatic phenomena and all we have done is a little work separating positive and negative charges and a whole new world is exposed to us and I thank you for watching [Music]