Khai thác bộ thí nghiệm Franck - Hertz để minh hoạ mô hình nguyên tử bo

II HUONG DAN QUAN LV, SU DUNG

KHAI THAC BO THI NGHIEM FRANCK - HERTZ

DE IVIINH HOA MO HINH NGUYEN TUT BO

TIlS. Tran Ba Trinli, Khoa Vdt li, TrUdng DHSP Hd Ngi

1. Dat van de

Hien nay, cdn nhieu kien

thflc chfla cd du hoac khdng cd

thi nghiem de nghien cflu. Do

dd, ben canh viec thiet ke, che tao

thi nghiem mdi hoac cai tien thi

nghiem da cd, chflng ta van phai

nhap mpt sd bd thi nghiem khd,

ddi hoi cdng nghe che tao cao do

nfldc ngoai san xuat de bd sung,

hoan thien he thdng thi nghiem

vat li P trfldng phd thdng. Cac

thiet bi nay hien dai, chae chin,

ben dep va cho ket qua chinh xac

nhflng khd khan trong sfl dung

vi tai Ueu hfldng dan, thdng tin

tren cac dung cu thi nghiem

bang tieng nfldc ngoai va mat

khac, rat dat tien. Khai thac cac

bp tbi nghiem nay trong day hpc

sao cho hieu qua dang la van de

can dflpc quan tam.

ChflPng "Lflpng tfl anh

sang" bao gdm cac kien thflc ve

hien tflpng, quy luat, tInh chat vi

md cua anh sang, nhfl gia thuyet

Iflpng tfl nang Iflpng cua Plang,

md binb nguyen tfl Bo,...la nhflng

md hinh li thuyet trflu tflpng,

can dflpc kiem chflng, minh

hpa bing thi nghiem. Tuy nhien,

trong phdng thi nghiem \'at li phd

thong, chfla co bd thi nghiem

nghien cflu cac kien thflc nay. Bai

bao trinh bay ket qua khai thac

bd thi nghiem Franck - Hertz do

hang PH'i'^VE san xuat, cho phep

tien hanh thi nghiem lich sfl cua

Franck va Hertz de dfla ra nhflng

bang chflng thflc nghiem eho mo

hinh nguyen tfl Bo; dong thdi

de xuat kha nang sfl dung bd thi

nghiem nay trong day hpc.

.\hdn bdi ngd\' 25 4 2011

2. Khai thac bo thi nghiem

Franck - Hertz

a) PhUdng dn thi nghiem

Franck - Hertz

Ben trong dng chfla hoi thuy

ngan (Hg) binb tru, Catdt K bi dot

ndng bdi hieu dien the Uj^. Cac

electron bflc xa nhiet tfl K dflpc

gia tdc bdi hieu dien the U^ gifla

.\n6t A va Catot; A la mdt Ifldi

hinh tru. Tren quang dfldng tu'

A den cflc dem S, electron bi can

trd bdi dien trfldng ngflpc sinh ra

tfl hieu dien the U,. Gifl U„, U,

khong doi, tang dan U^; do ddng

dien I^ tflpng flng trong mach; ve

dd thi I^ - U, de phan ticb chuyen

ddng cua electron trong dng,

qua dd, nghien cflu va cham cua

elentron vdi nguyen tfl Hg.

6V

Hai thiiy ngan

^ 0

/77

Ut U2

0„nV 2V

Hmh 1. Sddd thi nghiem Franck - Hertz

b) Bo tri vd tien hdnh thi n^iem

- Bd van hanh (Hinh 2b)

cung cap cac hieu dien the U^,

U^, U,j thdng qua day cap 5 dau

tdi ban mach gan dng thuy n^an

(Hinh 2a) theo so do hlnh 1. Ong

thuy ngan dat trong Id nung F -

H (Hlnh 2c), d nhiet dp khoang

ISO'C de thuy ngan tdn tai dflpc

d trang thai hoi. Tin hieu ve ddng

dien I^, nhiet dp Id (dflpc do bang

nhiet ke nhiet dien NiCr - Ni)

dflpc chuyen lai va hien thi d bd

van hanh qua cap thdng tin BNC.

CofCrjl IMi! 9«'-»'^

- o

I tt» %

o <^ o

(c)

Hmh 2. Bo thi nghiem Francis - Hertz

- Cd the thu thap va xfl li sd

Ueu theo ba each. Cach 1: Chinh

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