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i fue 10! rahoact' ele chanism =. aXe => & \- Ae EE aM — eget Np 3 ol energy ; se) 2 ‘Ameritictun, Be eae | _ Coarent nveli) jseetugater val) | When. ‘alpha emission occurs , the peter number decreases. by a | 3. nuclear nvmber. decreases by 4. Alpha particle 13 the _ - helivm. nvcle vs but | not | ‘atom as it does not have any e7 | GRR aiie emitting alpha & beta particles, nalevs have hee at nar, oHen it ANG ovt this energy by his radiation ig cahed” = eso vy nucleys < ? ?O- augered from| nucleus Ww migh speed. M eckgnism, = AK | Grete La + | se ot efiergy & In beta decay, a neviton in the uclevs splits off in a proton bon electson. The proton stayed inthe nuclevs D tne electron U is esected from the nucles at hy need. Tati Scanned with CamScanner | “negatively: cael “no lead. ‘asit is an. — particles <_ | AMT te wave. Bast! moving, tia | id ay an ees romana wave with |high re fre _B Short | eel nH ‘Is been ‘identified as a stream of helm nucli.in other words, alpha partici? Ss actually a positively _ Charged cee se ame of 2 protons & 2 nevions a Alpha particle ‘is hia qnly antsing We produces. many, vons per millimetre along is path. le "aa range. of alpha cadiadion is| limited! 8) ie cael -__5-6icm of air or by thin paper . | | -@Speed of alpha in air 1s |O'm/s = @Alpha particle is deflected mn an electric 2 magnelic fiek, ‘ike! a positively charged Aaaie & Follows Figmings LHR. | of * Electric Field Scanned with CamScanner in the diagram rhe gold tea clectroscope is +Vely charged % initially ehe {eat 2 plate are ina diverse position! ao \idxe nar ges repel each other wren the source of radiation I's SA neay the cap of tho charged elecktoscope, the radiakon emitted vonises tha air moleqies above tha cap. The like charged air MOLARS. dre repelled by tHe cap while tho uniske Cyarges are attyacied +0 wards it-On reaching $ho cap, the alike charged ions neutralise the charges on tho |. glettroscope Therefore the gold leaf collapses . Same vesvits are opserved for all tha 3 Yadiation. So wth old leat electos cope .we Can.only detect whe tov a sovvce 1§ rad{Oackive OT NOt, bYt the type OF tadiation Cannot be — erected. 4 Scanned with CamScanner are PII i ( coho black ani are | | |_| EE He -Radution emitted boy. the source ionises ine + Alcohol vapour condenses dver tne See hey \ | 35 white dots | against the black | acl at ii (4 | | | { “Tra Tracks observed for abha particle: serve Tracks opserved for abha particle ne a cles _=straight & thick | | (eile ( [« particles are han ionising B _| mass ive ] ja | Jessel TRACKS FOR ALPHA —Sshort ey has short range in sill if bracks are of different length , +e particles have different kinetic energy -/f all tho partictes |have: same | lanetic energy , the ane will be of Same! leng tn erved fov beta particles = iwisted %& ‘ihinner Cocta particles easily deviated by Cojfisions. with vapovr Mokcu ies, | | as lighter nan & 3 less TRACKS FOR RETA. ionising than a | —longer [ P has lon range in air] sacks observed for gommd. par see = short, Enin } irregular M [gamma radiations are least TRACKS FOR GAMMA 8 eavily deviated] A Sometimes the tacks formed by bea & gamma tadiation look simmlay 50 _diffievilt to identify with cloud chamber, ick Se ake Source |_| GM tube} | |} | Esa Boat Be: Soe eek oe re a See _Backgiound Radiation > When the radiation sovree fo | removed), the! GM tbe. usually egisket._g count. of between “= 20-50 counts per minvté -This-phenomend 1S known as tne backgsoun4 “count, which \s dveto \backgtound vadiation\ | _ — | | i | -| t i 4 j i | Pala | } | | [es | | S — tay [tis Caused by the radioactive contamination of the |_| ‘detector or! i's | svrcoundings 14 can also be dve fo cosmic? fadiation entering the (earths atmosphere | ftom outer __-— ‘space. It iS also idve Earth’ crust. | es: "| Mackgmum count 2 50 covnts/mio With Source Count — 4000 counts/min Peal a [chin piece of paper Hell tA aaah ae BEE FO. ENGOO TEs » Count sate dropped significant drop in to background . count rate.So,alpha__. change. *Only Alpna present present aS dipha tS _ *So,no alpha Stopped by paper. alominim “SHill_count 1a® 1s jal well above backgrourd 100 90.0) 700 i So,there mnt be ben orgamma or both jalununium L V 50 .4OO jee “1415 dropped +0 background > Significan’ drop in Count rate... “Reta is present. - _$o, Beta present as Meta is _ * No.gamma Stopped by Aluminium 550 * Still wel above background - “No Reta So, @amma Is also present | Scanned with = | Ba a Bia eisai | potest [Count Rate drops to background. 7S, Gamina present - whith iis stopped by Ie lead é in jece of paper —>Alpha cai) pin p thick: ‘pane > ane 2am thitk lead —> Gramma oa Epetiqent.. for. Alpha Smention/-use of thin. paper _Pcount rate una to background fe bts + ——tmagnetic ‘field is placed between | * count Yate drops sig gnificantty ____* beta parties are charged 2 are Hoan terdaa } vee OF paper by magnetic Field ~so do not Stopped buy paperso reach the G&M tube” -wexperiment for Gamma magnetic field placed between _ * fo signi€tcant change- of count rate *gamnia_radiation is yncharged,so is not defiedced . N= No- of meat atoms Rate ie a Sy Activity /a Scanned with CamScanner _— ca — Before | sorting te experiment _backgtourd. “count is. "no: Tene mM tbe withouk tne Aes _ of EEN Isocere of radiation, in, cho! sinrondiegs. the coun} tates) in the thovon 4 ned ex periment then ze Toneded bs. substiacting the Yoverage. backgtoynd lcount. rate, Yom eath Yogding, | + | “| Aaroph GF | the corte cted count Ytate /activity ae — F10ne 1S pored: & the. halfli€e’ (5 estimates ffm it a Ae ines oe | | | 4. Ao 2 initial ea ala _Aniz f final activ nw = ino. ee ee | Half ue oat 70. Ex:1 > ‘Wihal achivity (000, hate life lis! Bi bee Whak is tne’ | Final Activity after (S hrs. no. of half liven = Tota’ Dec. half i flo = 1090 Ao \s4 and 1000 —, 500 —-> 250 —>1Q5 _ aig h oS See Ratertods Alpha particle _ Feattering Exp aap J eae ee teak Or | He i REE £ Marsden aeeseS Experiment aaa Scanned with ce) CamScanner iS saa | | | | op | 2 | 4 our of 006 : Weal aa Abobnte. back — SS alee | ia AES Sal + trend) expecimant: =n = ioa Ls = z = tes a Tle cr eo Observation lof! A PSSRa pata eee ees ac of thé aipln ~ [paricles|went_strat he theuginl p the god Soit, without Pais change io eel ae at “4 = 1dss 4 5 ed| | IX ae onegy Co fae “deviat aes 1hon30) 1g ail i > Very Fe alpha particles, A “A in. 8000 ate | | : ad ‘al yD “90 04 i,a aaron “480° | | : eval by more than. PP | a ieee a = _lconciveions from the aoe aisthvawios SS Eel See mee el eee | | til | | i : ft al T_The majority, oF MW particles were unde vrated, oy Sight! “Li beviated i 8 ests. that there exists | a. sarge ertPy g Se in| an. Qtr - Ter: efo (e, | most: of an atom: is empty Space. = i s| sa seca fo 2 ‘Alpha “porticies have masses more. “Anan ‘electrons. So. | “et / alpha lave Imossive _pgrticles, $0 whatever deflected a | To al would Teed, to have more Mass thar alphas | = sei charged Ta Ee gees ses HSE aes Only few alpha particles are eboun ced. back , showing ‘that. thé positively dnarged dense cove, pasa Known “as _huuevs, occupies _ne tignole space_in the alom& there ge a large distance _b tween the hopes Sth electrons P around _, — | } co! He = + Mos) of the atom's mass_.i¢ ‘oncentated i in the nucleus at the centre of the atom. | | | Pee *Uo1p pad UOISS er ~ gnataau @ $1 SI + pases OSTE We suo ItAaY aay yg uodhiy ~agwqueg Blainu sub om OU suds J IIGe+SUN st YUM ‘9 ¢g-wiluesq Sw303 4! %suonnau hq papieqwog si py 3M uononpord hhsaua seapnu soy tagaso st GEz wnUesn ST Siloy GET — Watuesy pw Lo Wig 8ez- sag) yoiym ée sadojagr JO —aanyewud & SUBIOY wUMUeIA DUIII270~ hyeinteny “Absaua—a20po3d : O4 da yeaiq StejIM ajqessun hweay Qraym Ssqvoid uy SiH Ei 95 we ~ hbsa ty26+ OS + Od ye — Ut Necz =~ | cher gues 94} hy ayew xordde jo tayau sary bu zt out saaynu tweay 30 huymds yo ssaroxd ayp si uolssi) JeanaN SS (ssoy 10. vieb) ssew ut abuew =Wy - el (ssoj 20 web) hOxque we auew-3V ee i Wate jo pads =9° by ul ssw = Ww sqnof ur GG aqua = peed = Sous SRM ‘aig hq passaidxa oq _ueD pue uajexinta == aap hhiaus pue ssew qeur vorsebbas e apew urpsuly =| 2 WIZ 4 209} 20N ‘eS eahetieet = (tweets W)-w= Wy = eal ~ BSD Ss Peed sen) | TSA ie ee wml ify 30 (ee) | swale sseyry Cus fw tw cw )- ed) ea ie ie SCeSe Rese ea \ ' i EUS oN STS REST aE a La Most of the eneygy on earth comes from the sun || °» lee where it 1S produced by Avcledr Fusion ceaction Q-—B® mamem m+M2>Mm) |_| Mass Defeat = (mimz) 7m = A€ #? Om Ct |e [Ba (ioe: é ‘ers released in fusion aH + 7H —s SHe + oN tenergy | aa Nuclear fusion is the process where lignite fvdelis fuse | together 10 form a heavier nucleus with a@rejease of energy.” The EnEvQy released in again dux to the loss of mass of ~) mass defect, which 's Given by the total mass of the lighte = _ woe! des minus the mass gf th? hoavet Nvciens Lormed. _ QGove_A00"rmuttion °C > 1 Ms_tre process fy whith a Differences - = Phe flemperabore needed to mare. nuclear fosin is Cun produces energy. fo ad high speed ove F@mo- repulsive force Défficvet 20 antrop — SS =u Sion F_rssiion Reason_ eduction én mass aihenl fragments of phe explosion _ fit___| aight nockkiare fised __\ane of much tower mars Energy _| fogesnen : fhan' cwipinat _nucbeu. . PrOCeSS Two Gight nucler fase | @reahap of a heavy snetbCe fogether fo _form_o__|nucteys by bombardment sin gle_nucleos, by catsing with Ssbw_mourg Neutror>, fre_Eemperature, ehain_eeae fion enables. the anvclergre farovght __ jpracess. €o_be_capneéon., fhe. | Prsson of a. pvelevs, produced | enough Meutrons 10 aapse _tore- frseian_of Another nuclei- Gan be omtrolted. TUMSeS oF -Rabinbionte Tt te ~ ™ Radioative materials are being vsed in main diferent ways —in medicine, indvebry % agrievt Ure. 7 | They are used a tracers, as penesrat ing cadvation, as power Sources, for medical -treatment %- for ar chaeO— & 4 =loqical dating. t flTpaceps : | Finding) leakage in pipes — Ry énfroduceng a svibable _ Madiodcbive racer cnto he pipes. a tedk can he — J found eorily ty means of a GH tube etichevil , Pegester an “tensixoa te a count fafe attne area of ~ Fhe teak Thus svebe tn ime 8 money tn .repaicing % torating. tha teak. | share pales! . pop {O00 T. — hm i Ey counter tbe = Soil 4 F 7 Underground --_.- - => a Tain es ? The GM “tubes withou' the pak ane detects backgrovna Aichi ‘Source. of sadialiion—> Beta *pipha & Gemma —> same seading _ a _. nor peneirate penetrate hvowgh through soil & pipe both so) B pipe In. agriculture , radioactive phosphorus- 32 is wed as = dyacr 10 Find ovt how well the planis ave absor bin _ phosphates whiUn are crucial 10 their Qrowth.The 2) © complicated anechanim of photosynthesis has also been Studied using tracers . be | ! | | } } Bee sezyeguuee qua: J LJP eMC ePe geno alpho. BE o00 zs |_Pannotpenetratd. = i ES EES | TOTOTDE astute | || fete] Ce Agoo, eles ie eee ~ __ Covnts_per voit time S fiickness — eee @oller pressure & thickness | Aba | Surtable radioactive somes are wed to check the themes of roll_sheetS oF metal, paper or plastic ‘The aboye diagram shows_ _the otangemont .The Munt rate vecened by the detector = | depends ‘on ‘how much radiation can. (ee i Se | material -The greater the_ thickness, the lower 16 the __ — ont rate % ‘vice versa . Thus If tne cunt mie detected _ | is constant _,tnen it is concluded that the thickness 1s __ ~ Weonstantl. | Vo PAS ee ee Gramvra_sovrce iS _ysed 10 control the ibickness of steel plates . Bela sovrce is sed 10 check the thicknes of paper % pbsiic. ‘in the food indusiry .the high penetration power of amira_ says 15_vsed_{o toil on bacteria in pre-p a = frozen food. This wilt sterilize the Food 2 prevent od __ poisoning. 
