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    Counts in a geiger counter

    Thank you all for detailed answers. In this connection, I think I can take the privilege of placing some more questions. I have read that more than two or more alpha or beta particles or one alpha and one beta particle will not be emitted by an atom simultaneously. They will be always...
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    Counts in a geiger counter

    One thing is not clear to me. When alpha or beta or gamma radiation enter into geiger counter, it ionizes the gas and ionization current produces counts in the detector. What exactly this counts indicate? Does it show the number of alpha or beta particles enter into the tube? Since even if one...
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    Why canal rays need a perforated cathode?

    Thanks for the reply.Sorry for my delayed response. Regarding the above statement, I could understand the light rays being scattered by an object. But how does it happen in the case of cathode rays? The latter being negative, when they hit the positive anode, will they not be attracted...
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    Why canal rays need a perforated cathode?

    In the cathode ray production experiment, at about .01 mm of Hg, cathode rays travel from cathode and move towards anode and produce fluorescence on the walls near the anode.At the same time canal rays also move towards cathode. But only when you use a perforated cathode, the canal rays...
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    Ratio of charges in thomson expt

    Homework Statement three particles having charges 1:2:3 produce the same point on the photographic film in the thomson experiment. The masses are in the ratio of a) 1:2:3 b)3:2:1 c) 2:3:1 d) 1:3:2 Homework Equations a = F/m = Eq/m The Attempt at a Solution Since all the...
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    Seebeck effect

    In thermoelectric series, lead is arranged in the middle and other metals arranged both on the left and right hand side of lead. Lead does not exhibit Thomson effect. If you take a metal on the left of lead and another metal on its right, the thermo electric current flows according to certain...
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    Meissner effect

    Thank you DrDu. What I want to know is whether magnetic flux will pass through a diamagnetic metal as it passes with ease in a ferro or para magnetic material, since the permeability of a dia is too low when compared to a ferro. Because in many illustrations the first diagram shows penetration...
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    Meissner effect

    I need clarifications on Meissner effect. 1. According to this theory, when any diamagnetic substance is cooled below its critical temperature, it becomes a superconductor and it expels magnetic flux from inside. Is it applicable only to a diamagnetic substance or ferromagnetic substances...
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    Gauss theorem and the nature of the surface

    Thank you for the reply. If there is no lines of force, then how the calculated value of 1.129 x 10[SUP]11 lines of force from 1 C of charge placed in air or vacuum arrived? What does that number exactly stand for? The value has been obtained from the formula 1/ε for air.
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    Gauss theorem and the nature of the surface

    According to Gauss’ law the total number of lines of force over a closed surface is equal to 1/ε times the net charge enclosed within the closed surface. Why should it be a closed surface but not an open surface too? I am unable to find a convincing explanation for it. Since we take into...
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    Source of energy in fusion reactions

    In the case of nuclear fission, when U-235 splits into Ba,Kr and three neutrons , then it is shown that the total mass of the products on the right side of the equation is slightly less than that of the reactants on the left side. So this missing mass-the mass defect – is converted into energy...
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    Higgs boson and the future of quantum phyiscs

    Thanks for the reply. A little more elaborate discussion is welcome. What I want to clarify is that whether the recent discovery confirms the particle nature of the field. Which means then that the field is not continuous one as Einstein is said to believe strongly? Also I could not...
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    Higgs boson and the future of quantum phyiscs

    Can anybody throw light on the following doubts? 1.what is the implication of the recent discovery of the higgs boson in the quantum physics? Does it support the quantum nature of matter and wave and the uncertainty principle? 2. It is said that Einstein did not accept the quantum theory...
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    Alpha ray scattering experiment

    I have some basic doubts in the alpha ray scattering experiment by Rutherford and his students way back in 1909. 1.In the formula for the distance of the closest approach, the term velocity of the alpha particle and the charge of the gold nucleus appears. How did they measure the velocity of...
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    Polaroids in head lights

    I have studied,as one of the uses of polaroids is, that it can be fitted in the head lights of cars and other vehicles to eliminate the glare. This will certainly act as a boon to the motorists and result in considerable reduction of road accidents during the night time. I have also learnt...
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    Carbon di oxide emission of filament bulbs

    May be it is because, when people use the filament bulbs, a lot of energy consumed goes into air as heat. But, it is not the case with the CFLs. So, can we say that the burning of the filament bulbs contributes to the increase in the air temperature, thereby contributes to the global warming? I...
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    Carbon di oxide emission of filament bulbs

    Sorry. I couldn't catch what you wanted to convey.
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    Carbon di oxide emission of filament bulbs

    One thing I am not able to understand. Governments advocate the slow phasing out of the filament lamps and replacing them with CFLs.The reason repeatedly cited for this is that the filament lamps contribute to the global warming by way of emitting carbon-di-oxide. But, interestingly, it is...
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    Cathode ray tube

    Thank you for all the replies.
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    Cathode ray tube

    Thank you for your reply. Even if there is some traces of air, will it glow green, when struck by electrons? Regarding the (2) and (3) I have given the video links below. (2) (3)http://www.youtube.com/watch?v=Xt7ZWEDZ_GI&feature=results_video&playnext=1&list=PL1559C68545F8F4A1
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    Cathode ray tube

    In a video demonstration (not animation), cathode rays appear as a beam of green light moving from the cathode to anode inside the tube. The demonstrator brings a magnet near the tube and the green beam deflects. This I can understand. What I can not understand is that how the electron beam...
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    NASA Slowing of a satellite sent by Nasa

    Thanks for all the answers. Sorry that I didn't visit this site for quite some time. What I understand from all these discussions is that the gravitational anomalies at different places on the earth may cause the phenomenon of speeding up or slowing down of a satellite in its orbit. It has...
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    Pre emphasis net work

    I will be thankful if any one clears the following doubts in the concept of pre-emphasis in a FM transmitter in a simple way. 1. In the higher secondary physics text book published by Tamil Nadu government, regarding the pre-emphasis net work, it is given as follows:"Since the modulating AF...
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    Output impedance

    The concept of output impedance is highly confusing to me. I will be thankful if some body gives simple explanations to the following. 1. I undertand that in the case of current amplifiers, the out put impedance should be low and the input one should be high. In the case of voltage...
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    Radio active decay

    I need some clarifications on the following concepts: 1.When an α-particle is released by a radio active sample, it loses a charge of +2. Similarly, when it loses a β particle it gains one positive charge. But there is no change in the number of electrons in the outer orbits of the radio...
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    Mass spectrometer

    When different masses are accelerated by the same potential,the lighter mass should move with a greater velocity than that of the heavier one. But, how in the velocity selector in the Bainbridge mass spectrometer, different masses(isotopes) come out with same velocity?
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    He-Ne laser

    Thank you for your reply. I already went through the Wikipedia article on He Ne laser. But the answers to the specific doubts I have raised above are not found in the article. The other articles are too lengthy and complex to follow and understand. If any body who has understood the topic very...
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    He-Ne laser

    I have some serious doubts regarding He-Ne laser: 1. In He, the ground state energy value is taken is 0 eV and the meta stable state is taken as 20.61 eV. similarly in Ne the meta stable levels are taken as 20.66 and 18.7 eV respectively. How these values are arrived at? In Bohr's expression...
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