Piv txwv ntawm Cov Lus Nug Sib Tham Txog X-ray
Cov duab xoo hluav taws xob, feem ntau hu ua rontgens, yog ib qho thev naus laus zis tshiab hauv kev kho mob thiab kev lag luam. Txij li thaum Wilhelm Conrad Röntgen tau tshawb pom lawv hauv xyoo 1895, cov duab xoo hluav taws xob tau qhib lub qhov rais loj rau cov kws tshawb fawb thiab cov kws kho mob kom pom cov qauv sab hauv ntawm cov khoom yam tsis ua rau lawv puas tsuaj. Txawm li cas los xij, kev nkag siab txog lawv cov ntsiab cai ua haujlwm thiab kev siv yog qhov nyuaj. Yog li ntawd, tsab xov xwm no yuav tham txog cov teeb meem piv txwv uas cuam tshuam nrog X-rays los pab piav qhia txog yuav siv cov thev naus laus zis no li cas hauv ntau qhov xwm txheej.
Keeb Kwm thiab Cov Ntsiab Cai Tseem Ceeb ntawm X-Rays
Ua ntej yuav mus rau cov teeb meem piv txwv, nws yog ib qho tseem ceeb kom nkag siab txog cov hauv paus. X-rays yog ib hom hluav taws xob electromagnetic uas muaj qhov wavelength luv heev, uas ua rau lawv nkag mus rau ntau yam khoom siv. Qhov no yog qhov ua rau X-rays muaj peev xwm pom cov khoom khov kho, xws li pob txha hauv tib neeg lub cev.
Lub hauv paus ntsiab lus ntawm X-rays yog raws li kev sib cuam tshuam ntawm cov rays thiab cov khoom. Thaum X-rays hla dhau ib yam khoom, qee qhov raug nqus thaum lwm qhov raug xa mus. Cov khoom ntom ntom, xws li pob txha, nqus tau ntau dua X-rays dua li cov nqaij mos, xws li cov leeg thiab daim tawv nqaij. Qhov sib txawv no tsim ib daim duab uas tso cai rau peb pom cov qauv sab hauv.
Piv Txwv Lo Lus Nug 1: Xam Qhov Koob Tshuaj X-Ray
Lo lus nug
Ib tug neeg mob yuav raug kuaj X-ray nrog rau qhov koob tshuaj X-ray ntawm 0.03 Gray (Gy). Yog tias tag nrho lub zog uas tus neeg mob lub cev nqus tau yog 1.5 Joules (J), xam tus neeg mob lub cev hnyav uas raug rau X-rays.
Kev daws teeb meem
Cov tshuaj tua hluav taws xob (D) tuaj yeem suav tau los ntawm kev siv cov mis:
\[ D = \frac{E}{m} \]
Qhov twg,
– \( D \) yog qhov koob tshuaj hauv Gy,
- \(E \) yog lub zog nqus hauv Joules,
- \(m\) yog qhov hnyav hauv kilograms (kg).
Yuav nrhiav tau qhov hnyav ntawm lub cev (\( m \)), peb tuaj yeem hloov cov mis saum toj no rau:
\[ m = \frac{E}{D} \]
Hloov cov nqi uas paub lawm:
\[ m = \frac{1.5 J}{0.03 Gy}} \]
Nco ntsoov tias 1 Gy = 1 J/kg, ces:
\[ m = \frac{1.5}{0.03} \text{ kg} \]
\[ m = 50 \text{ kg} \]
Yog li, qhov hnyav ntawm tus neeg mob uas raug rau X-rays yog 50 kg.
Piv txwv lus nug 2: Kev txheeb xyuas cov nqaij siv X-Rays
Lo lus nug
Hauv daim duab X-ray, pob txha zoo li ci dua li cov nqaij mos. Piav qhia vim li cas qhov no tshwm sim hauv cov ntsiab lus ntawm X-rays cuam tshuam nrog ntau hom nqaij sib txawv.
Kev daws teeb meem
Cov duab X-ray ua haujlwm raws li qhov sib txawv ntawm kev nqus ntawm ntau hom nqaij sib txawv. Pob txha muaj qhov ceev thiab tus lej atomic ntau dua li cov nqaij mos xws li cov leeg. Yog li ntawd, pob txha muaj txiaj ntsig zoo dua ntawm kev nqus cov duab X-ray.
– Pob Txha: Vim nws ntom thiab muaj cov khoom uas muaj cov lej atomic siab xws li calcium, pob txha nqus tau ntau cov duab X-rays. Qhov no ua rau muaj tsawg dua cov duab X-rays mus txog zaj duab xis lossis lub tshuab ntes, ua rau thaj chaw ci dua hauv daim duab.
– Cov Nqaij Mos: Cov nqaij mos xws li cov leeg nqaij thiab daim tawv nqaij muaj qhov ceev thiab tus lej atomic qis dua. Lawv tsis nqus ntau cov duab X-rays, yog li ntau cov duab X-rays raug xa mus rau zaj duab xis lossis lub tshuab ntes. Qhov no ua rau cov cheeb tsam nqaij mos zoo li tsaus dua hauv daim duab.
Cov kev sib txawv ntawm cov xim lossis qhov kaj no tso cai rau tus kws kho mob lossis tus kws kho mob kom yooj yim txheeb xyuas cov qauv hauv lub cev.
Piv txwv 3: Xam qhov ntev ntawm cov duab X-Rays
Lo lus nug
Yog tias lub zog X-ray muaj zog li 124 keV (kilo-electronvolts), xam nws qhov wavelength. Siv cov mis:
\[ E = \frac{hc}{\lambda} \]
Qhov twg,
- \( E \) yog lub zog (hauv joules),
- \( h \) yog Planck tus nqi tas mus li, uas yog \( 6.626 \times 10^{-34} \) J·s (joule-seconds),
- \( c \) yog qhov ceev ntawm lub teeb, uas yog \( 3 \times 10^8 \) m/s (meters ib ob),
- \( \lambda \) yog qhov wavelength (hauv meters).
Kev daws teeb meem
Ua ntej hloov lub zog los ntawm keV mus rau joules. 1 eV (electronvolt) = \( 1.602 \times 10^{-19} \) J, ces:
\[ E = 124 \times 10^3 \text{ eV} = 124 \times 10^3 \times 1.602 \times 10^{-19} \text{ J} \]
\[ E = 1.985 \times 10^{-14} \text{ J} \]
Los ntawm kev siv cov mis:
\[ \lambda = \frac{hc}{E} \]
Hloov cov nqi uas paub lawm:
\[ \lambda = \frac{6.626 \times 10^{-34} \text{ J·s} \times 3 \times 10^8 \text{ m/s}}{1.985 \times 10^{-14} \text{ J}} \]
Kev suav:
\[ \lambda = \frac{1.9878 \times 10^{-25}}{1.985 \times 10^{-14}} \text{ m} \]
\[ \lambda \approx 1.002 \times 10^{-11} \text{ m} \]
Yog li, qhov wavelength ntawm X-ray nrog lub zog ntawm 124 keV yog li 1.002 \times 10^{-11} \) meters lossis 0.1002 nm (nanometers).
Piv txwv lus nug 4: Kev siv cov duab X-ray hauv kev kho mob
Lo lus nug
Ib tug neeg mob raug kuaj pom tias muaj pob txha caj npab tawg thiab yuav tsum tau thaij duab x-ray. Yog tias siv duab x-ray nrog lub raj fais fab ntawm 100 kV thiab tam sim no ntawm 10 mA rau 0.1 vib nas this, tag nrho cov nqi hluav taws xob ntws los ntawm lub raj yog dab tsi?
Kev daws teeb meem
Tus nqi ntawm cov nqi (Q) tuaj yeem suav los ntawm kev siv cov qauv:
\[ Q = I \times t \]
Qhov twg,
- \(Q\) yog tag nrho cov nqi hauv coulombs (C),
- \( Kuv \) yog tam sim no hauv amperes (A),
- \( t \) yog lub sijhawm hauv vib nas this (s).
Hloov cov nqi uas paub lawm:
\[ Kuv = 10 mA = 10 lub sijhawm 10^{-3} \text{ A} = 0.01 \text{ A} \]
\[ t = 0.1 \text{ s} \]
\[ Q = 0.01 \text{ A} \times 0.1 \text{ s} \]
\[ Q = 0.001 \text{ C} \]
Yog li, tag nrho cov nqi ntws los ntawm lub raj yog 0.001 coulombs.
Xaus
Qhov teeb meem piv txwv saum toj no qhia txog ntau yam kev siv tshuab uas siv tau rau kev siv X-rays, suav nrog kev xam cov koob tshuaj, qhov ntev ntawm lub teeb, thiab tag nrho cov nqi. Yog li, kev nkag siab txog cov ntsiab lus yooj yim thiab cov ntsiab cai ua haujlwm ntawm X-rays tuaj yeem siv los daws cov teeb meem nyuaj thiab tshwj xeeb dua. Kev paub txog cov ntaub ntawv no yog qhov tseem ceeb rau txhua tus kws kho mob ua haujlwm hauv kev kho mob hluav taws xob, tshuaj, lossis kev tsim kho nuclear kom ntseeg tau tias kev siv X-rays muaj kev nyab xeeb thiab zoo.
