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ELECTRIC CHARGE AND FIELD, (6.) The body, Loosing some of its electrons and Can be charged, negatively by gaining electrons., 1., or atom can be charged positively by, Electric Charge -, it exests, s called the electric charge., The property of material by which, or experience electric omd magnetic etfects, to detect charge, (7:) The apparatus used, " Gold leaf Electroscope"., body, on, is, E kamples -, O Expesience of seeing, hen we take of ar synthetic cloths., a spark or hearing, a crackle,, Charged, Glass Rod, Metal Foil, (ii) Lightning in the sky during thumderstorms adue to, eiectric alischasge., Cork, Copper wire, Electrostatics -, gold leaf-, branch ok Physics, which deals, resto (static charges),, The, cith the studly of charges at, the torres , kields amd potential due to these charges, iA called Electrostatics, glass jar., or static Elect ricity., (8.) An electric charge can creates electric tield (E ),, magnetic field 3) amd electromagnetic radiations, Important Facts about charge, V =O, (1.) There, are only tuo types of electric charge., 2.) Like charges repel cmd unlike charges attyacts each, -→ Only Electric tield (E), Cther., V = Const., » Electric Field (E) 4 Magnetic Field (B), .3) The unlike charges nullity ( Cancel ) each other's effect, in Contact. Therefore the charges, when they Come, named as, scientist 'Benjamin Frenklin!, v + Const., positive omd negative by the American, amd Electromagnetic Radiations, Normally the materials are electrically neutral, they, do net Contain charge because their charges (Protoxs, nd electrons) are exactly balanced., (9.) Electric charge unitormly distribute on, sustace but +the charge děnsity, surtace, of curve is minimum., umiform, non- unitorm, on that ' points where the Yadius, on a, is maximum, E) The electrori of the outermust orbit ok an atom, are far trom the nucleus, cosely bounded with the nucleus md can be, Separated easily from the crbit by giring some energy., nese electrom are then called ree electrons., So these electrons are, Chauge olensity

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Everything is made of atoms. The basic components of atoms are, Properties of Electric Charge, protons, neutrons and electrons., Otheeee, (1) Additivity of Charges:-, Electric, charge is, scalar quantity se, the total charge of the system vis obtained sinipiu, by adding the different charges algebrica!lly with, proper sign according to their c, I'm neutron.., I'm neutral, charge, Hi I'mproton!, I'm positive!, I'm elestron, •2,, 2, + 9, +...., negatire, · 23, • ?n, Point Charge-, It is a point where all the charge, (2), Charge is, Conserved :-, of a body is Concentrated!, distroyed. It, to another. Hence, can not be either Created, Charge, čan only be transterred from ome body, Conductor, Insulator, 4 Semiconductor, total charge of the isolated, the, system, always, Conselved., is, Conductor -, The material, charge amd current, thoough which the electric, are called Conductors., + + + + +, can flow edsily, Glass, silk, Calass, silk, Examples -, All Metals, Human body, earthh etc., To tal charge, O+o = O, Total charge, +9 -9 = 0, %3D, Insulator -, (3) Quantisation of Charge, :-, The materials which resist the, flow of, electric charge omd cusrent are called insulators., electric charge, an integral multiple of e( charge on, This is called quantisation of charge., The, body is always, I electiom), on, Examples -, Wood, Porcelene, plastic, etc., Semiconductors-, Q = tne, o, 1,2.... 00, The materials which resist the How, e =, 1. G02 X10 r9 c, of electric charge and current but the value of their, resistance is in between the Conductor amd insulator are, called semiconductors., Examples - silicon (si), * The unit of electric charge is coulomb., Coulomb -, Germenium ( Ge), - Excellent thermal Condluctivity., Carbon CC), total charge on 6.24 x1o'8, electrons is equal to, The, coulomb.

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Methods of Charging, IJ Charging by Friction -, when, two objects are rubbed against each other, then electrons from the atoms of one object ( having low, work function) go to other object ( having high work function)., The material looses electrons gets positively charged and, the material gains electrons gets negatively charged., (a), (d), (i) The ground Connection, (iv) The positive rod is removed leaving the sphare, with 'an induud negative charge., is, broken., Method 2., plastic, (i) Tuo uncharged metal sphares, each other but insulated trom rest of the uor's, are, in Contact with, sillk, (ii) A poditively charged rod is brought neas the, sphahe, attracting negatire charge amd leaving, the other sphare positively charged., 2J Charging by conduction -, when a charged object is brought in contact, with an uncharged conductor, then the same type of, change spreads on both the conductors. This hapbens because, are transfe rred at, Some, electrons, the Contact point., la), (h), C), (a,, (ii) Now, is removed, Charge., the sphares are separated betore the o, omd thus separating positive 4 nemtie, Unchanged Cherged, both positively charged, In Contact, (iv), Remove, the, rearrange themselves, the sphares., rod. The charges on spharcs u, omd umitormly distributed over, 3] Charging by Induction, Method, ( Using, 1., ground Connection ), (i A positively charged rod is brought near a neutral, metal sphare amd polarising it., (ii) The, be, sphare is grounoled allowing electrons to, att racteol from the earth.

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1Q.1, Two point charges of, (K) -, Dielectric Constant, + 2 Uc cmd +6uc repel, other with a force of 12 N. Now it each is, what will be, each, 9,22, given an additional charge of - 4 MC ,, the new force ?, force in a medium (Fm) =, 4JIE, where E - electrical permittivity of the medium., Here, 2, = + 2 uc, 92 = +6 MC, F = 12 N, force in vacuum ( F.) =, x 2,92, y2, and, 9, = + 2- 4 : -2MC, = +6 -4, = 2 uc, 4TIE., Dividing eq., (2), by, get-, we, = 2)(2), (2)(6), So, F, Fo, Fm, Er, or k, E., 4 N (Attractive), where E, or K is called dielectric constant oY relative, electrical permittivity ot the medium., w/, w/, A charge q is placed at the centre of the line, joining tuo equal charges,Q. show that the system, t three chariges will be in equillibrium it 9=-0/4., * Dielectric Constant ot a medium is the ratio of absolute, electrical permittivity ob the medium to the, permittivity of free space., electrical, SOL, * Thus force between two given changes in a medium, (K) is only times ot the force between them, air/ vacuum., A, Let two equal charges, 2x, Cnd B, where, AB = 23x., Fo, C is the centre of AB , where charge q is held., Fm, %3D, Here, K, Net force on, 9 is zero., q is already in equilibrium., so, For the three charges to be in equilibrium, net force, CYn cach charge must be zero., Force between Mutiple charges, number of charges, sum of all the torces on tha!, e is -, Total tor ce on any charge due to, at rešt, Now, total force on, Q at, the vectur, other charges., is, K Q.Q, (2x)2, K Qq, charge due to, KG2, - kQ2, Fis, 92, Fiz, Hence, Proved., 93