Imibuzo Eyisibonelo Exoxa Ngomphumela We-Photoelectric
Umphumela we-photoelectric uyinto ebonakalayo echaza ukukhishwa kwama-electron ebusweni bento lapho ukukhanya noma imisebe ye-electromagnetic ikushaya. Ucwaningo olwenziwe ngu-Albert Einstein ekuqaleni kwekhulu lama-20 ludlale indima ebalulekile ekuchazeni lesi simo futhi lwaholela ekwamukelweni kwenkolelo-mbono ye-quantum yokukhanya. Lesi sihloko sizoxoxa ngezibonelo eziningana zezinkinga ezihlobene nomphumela we-photoelectric kanye nezincazelo eziningiliziwe zezixazululo zazo.
Umbono Oyisisekelo
Ngaphambi kokuthi siqhubekele ezinkingeni zesibonelo, ake sibukeze eminye imiqondo eyisisekelo ehlobene nomphumela we-photoelectric:
1. Amandla e-photon: Amandla e-photon anikezwa yi-equation \( E = h \nu \), lapho \( h \) kungukungaguquguquki kukaPlanck (\( h \approx 6.626 \times 10^{-34} \) Js) kanye \( \nu \) kungukuphindaphinda kokukhanya.
2. Umsebenzi womsebenzi (\( \phi \)): Umsebenzi womsebenzi amandla amancane adingekayo ukususa ama-electron ebusweni bezinto.
3. Amandla e-kinetic ama-electron: Ama-electron akhishwe anamandla e-kinetic anikezwe yi-equation \( KE = h \nu – \phi \).
Isibonelo Umbuzo 1
I-Soal
Ishidi lensimbi linomsebenzi wokusebenza ongu-\( 4.5 \) eV. Ukukhanya okunobude be-wavelength obungu-\( 200 \) nm kukhanya eshidini. Thola:
1. Amandla e-photon amuncwa yi-electron.
2. Ingabe ama-electron azokhishwa ebusweni bensimbi?
3. Uma kunjalo, iyini amandla amakhulu e-kinetic ama-electron akhishwe?
Isixazululo
1. Bala amandla e-photon (\( E \))
\[
E = \frac{hc}{\lambda}
\]
Lapho \( h \) kungukungaguquguquki kukaPlanck, \( c \) yijubane lokukhanya (\( c \cishe 3 \izikhathi 10^8 \) m/s), kanye \( \lambda \) yi-wavelength yokukhanya.
\[
E = \frac{6.626 \times 10^{-34} \text{ Js} \times 3 \times 10^8 \text{ m/s}}{200 \times 10^{-9} \text{ m}}
\]
\[
E = \frac{1.9878 \times 10^{-25} \text{ Js}}{200 \times 10^{-9} \text{ m}}
\]
\[
E = 9.939 \izikhathi 10^{-19} \umbhalo{J}
\]
Ukuze uguqulele ku-eV, sebenzisa \( 1 \text{ eV} = 1.602 \times 10^{-19} \text{ J} \).
\[
E = \frac{9.939 \times 10^{-19} \text{ J}}{1.602 \times 10^{-19} \text{ J/eV}}
\]
\[
E \cishe 6.2 \umbhalo{eV}
\]
2. Hlola ukuthi ama-electron azokhishwa yini
Ngenxa yokuthi amandla e-photon (6.2 eV) makhulu kunomsebenzi wokusebenza (4.5 eV), i-electron izokhishwa.
3. Bala amandla aphezulu e-kinetic ama-electron
\[
KE = E – \phi = 6.2 \umbhalo{ eV} – 4.5 \umbhalo{ eV} = 1.7 \umbhalo{ eV}
\]
Isibonelo Umbuzo 2
I-Soal
Ukukhanya okunemvamisa engu-\( 1.2 \times 10^{15} \) Hz kukhanya ebusweni bensimbi obunomsebenzi wokusebenza ongu-\( 3 \) eV. Thola:
1. Amandla e-photon amuncwa yi-electron.
2. Ingabe ama-electron azokhishwa ebusweni bensimbi?
3. Uma kunjalo, iyini amandla amakhulu e-kinetic ama-electron akhishwe?
Isixazululo
1. Bala amandla e-photon (\( E \))
\[
E = h \nu = 6.626 \izikhathi 10^{-34} \umbhalo{Js} \izikhathi 1.2 \izikhathi 10^{15} \umbhalo{Hz}
\]
\[
E = 7.9512 \izikhathi 10^{-19} \umbhalo{J}
\]
Ukuguqulwa kube yi-eV:
\[
E = \frac{7.9512 \times 10^{-19} \text{ J}}{1.602 \times 10^{-19} \text{ J/eV}}
\]
\[
E \cishe 4.97 \umbhalo{eV}
\]
2. Hlola ukuthi ama-electron azokhishwa yini
Ngenxa yokuthi amandla e-photon (4.97 eV) makhulu kunomsebenzi wokusebenza (3 eV), i-electron izokhishwa.
3. Bala amandla aphezulu e-kinetic ama-electron
\[
KE = E – \phi = 4.97 \umbhalo{ eV} – 3 \umbhalo{ eV} = 1.97 \umbhalo{ eV}
\]
Isibonelo Umbuzo 3
I-Soal
Ukukhanya kwe-UV okunobude be-wavelength obungu-\( 120 \) nm kushaya indawo yensimbi enomsebenzi wokusebenza ongu-\( 2.2 \) eV. Bala:
1. Amandla e-photon ku-eV.
2. Ingabe ama-electron azokhishwa ebusweni bensimbi?
3. Uma kunjalo, iyini amandla amakhulu e-kinetic ama-electron akhishwe?
Isixazululo
1. Bala amandla e-photon (\( E \))
\[
E = \frac{hc}{\lambda}
\]
\[
E = \frac{6.626 \times 10^{-34} \text{ Js} \times 3 \times 10^8 \text{ m/s}}{120 \times 10^{-9} \text{ m}}
\]
\[
E = \frac{1.9878 \times 10^{-25} \text{ Js}}{120 \times 10^{-9} \text{ m}}
\]
\[
E = 1.6565 \izikhathi 10^{-18} \umbhalo{J}
\]
Ukuguqulwa kube yi-eV:
\[
E = \frac{1.6565 \times 10^{-18} \text{ J}}{1.602 \times 10^{-19} \text{ J/eV}}
\]
\[
E \cishe 10.34 \umbhalo{eV}
\]
2. Hlola ukuthi ama-electron azokhishwa yini
Ngenxa yokuthi amandla e-photon (10.34 eV) makhulu kunomsebenzi wokusebenza (2.2 eV), i-electron izokhishwa.
3. Bala amandla aphezulu e-kinetic ama-electron
\[
KE = E – \phi = 10.34 \umbhalo{ eV} – 2.2 \umbhalo{ eV} = 8.14 \umbhalo{ eV}
\]
Isiphetho
Isenzakalo somphumela we-photoelectric singabonakaliswa ngezinkinga ezahlukahlukene zezibonelo lapho sibala khona amandla e-photon, sihlole ukuthi i-electron ingakhishwa yini, futhi silinganise amandla aphezulu e-kinetic e-electron ekhishwe. Ekuxazululeni inkinga ngayinye, sidinga ukuqaphela ngamayunithi angokwenyama kanye nokuguqulwa phakathi kwamayunithi (isb., kusukela kuma-joules kuya kuma-electronvolts). Ukuqonda okuqinile kanye nomkhuba ofanele kuzosisiza ukuba siqonde imiqondo eyisisekelo yomphumela we-photoelectric, okuyinsika ebalulekile ye-quantum physics.
