Misalan Tambayoyi 8 na Lalacewar Ido
1. Hanyar haske da ke nuna samuwar hoto ta hanyar ruwan tabarau na idon mai fama da ciwon ido an nuna ta a cikin hoton...
Tattaunawa
Rashin hangen nesa kusa, ko kuma myopia, wata cuta ce ta gani ta ido wadda ido ba zai iya ganin abubuwa masu nisa ba. Nisan da idon da idon da aka saba gani a sarari yake. Matsakaicin mutum mai idanu na yau da kullun yana da nisan da ba shi da iyaka.
Dalilin rashin ganin ido kusa da ido shine tsarin ruwan tabarau mai lanƙwasa (ɓangaren kwance na ƙwallon ido ya yi tsayi sosai) don haka tsawon hankali na tsarin ruwan tabarau na cornea ya ragu, wanda ke haifar da hasken haske daga wurare masu nisa a gaban ruwan tabarau. Hasken haske mara iyaka ba a mayar da hankali kan ruwan tabarau don haka ƙwayoyin jijiyoyi a cikin ruwan tabarau ba za su iya canza raƙuman haske zuwa siginar lantarki don a watsa su zuwa kwakwalwa ba.
Amsar da ta dace ita ce A.
2. Ani tana da matsalar ido (hyperopia). Wannan matsalar ido tana faruwa ne sakamakon...
A. Nisawar idon yana matsawa kusa da idon
B. Nisa daga idon yana juyawa daga idon.
C. Kusa da ido yana matsowa kusa da ido.
D. wurin kusa da idon yana juyawa daga idon
Tattaunawa
Ganin nesa , ko kuma hawan hangen nesa, wata matsala ce ta gani a ido wadda ido ba zai iya ganin kusa a sarari ba ko kuma wurin kusa ya bayyana a sarari. Wurin kusa shine mafi kusancin nisan da ido na yau da kullun zai iya gani a sarari. Matsakaicin mutumin da ke da idanu na yau da kullun yana da kusan santimita 25. Mutanen da ke da hangen nesa na iya ganin wurare masu nisa a sarari, don haka za a iya cewa a cikin hawan nesa , wurin kusa na ido yana juyawa daga ido.
Amsar da ta dace ita ce D.
3. Kalli hoton!
Wadanne nau'ikan lahani na ido da gilashin ido za su iya taimaka wa masu fama da waɗannan gilashin?
A. Ganin nesa da kuma ruwan tabarau mai lanƙwasa
B. Gilashin hangen nesa kusa da kuma ruwan tabarau masu lanƙwasa
C. Gilashin hangen nesa kusa da kuma ruwan tabarau masu lanƙwasa
D. Gilashin hangen nesa kusa da kuma masu lanƙwasa
Tattaunawa
Lalacewar ido a hoton da ke sama sune hangen nesa kusa ko kuma myopia, seyadda aka nuna zane-zanen hanyar hasken rana a hoton da ke gefe.
Ganin nesa kusa wata matsala ce ta gani ta ido wadda abubuwa masu nisa ke bayyana a sarari. Nisa ita ce nisan da ido na yau da kullun zai iya gani a sarari. Matsakaicin mutum mai idanu na yau da kullun yana da nisan da ba shi da iyaka.
Dalilin rashin ganin ido kusa da ido shine tsarin ruwan tabarau mai lanƙwasa (ɓangaren kwance na ƙwallon ido ya yi tsayi sosai) don haka tsawon hankali na tsarin ruwan tabarau na cornea ya ragu, wanda ke haifar da hasken haske daga wurare masu nisa a gaban ruwan tabarau. Hasken haske ba ya kan ruwan tabarau don haka ƙwayoyin jijiyoyi a cikin ruwan tabarau ba za su iya canza alkiblar haske ba. 
Waɗannan raƙuman haske suna zama siginar lantarki don a aika su zuwa kwakwalwa.
Ana iya mayar da hasken haske daidai kan retina idan aka sanya ruwan tabarau mai kauri a gaban ido. Ruwan tabarau mai bambanta yana taimakawa wajen yaɗa hasken ta yadda za a iya mayar da hankali kan retina daidai.
Amsar da ta dace ita ce B.
4. Ana iya ganin ingantaccen tsari na hoto a cikin lahani na ido na myopic a cikin hoton...
Tattaunawa
Ciwon gani kusa ko kuma myopia cuta ce ta gani ta ido wadda ido ba zai iya ganin abubuwa daga nesa ba.
Dalilin rashin ganin ido kusa da ido shine tsarin ruwan tabarau mai lanƙwasa (ɓangaren kwance na ƙwallon ido ya yi tsayi sosai) don haka tsawon hankali na tsarin ruwan tabarau na cornea ya ragu, wanda ke haifar da hasken haske daga wurare masu nisa a gaban ruwan tabarau. Hasken haske mara iyaka ba a mayar da hankali kan ruwan tabarau don haka ƙwayoyin jijiyoyi a cikin ruwan tabarau ba za su iya canza raƙuman haske zuwa siginar lantarki don a watsa su zuwa kwakwalwa ba.
Amsar da ta dace ita ce A.
5. Idan wani yana da lahani a ido wanda ya kai kusan santimita 50, kuma yana son yin karatu a nisan karatu na yau da kullun (25 cm), dole ne mutumin ya yi amfani da tabarau masu ƙarfin ruwan tabarau na….
A. ½ diopter
B. ¾ diopters
C. 1 ½ diopters
D. 2 diopters
Tattaunawa
Mutumin yana da hangen nesa saboda kusancinsa shine santimita 50. Matsakaicin kusancinsa shine santimita 25. Ana gyara hangen nesa ta amfani da ruwan tabarau mai lanƙwasa. Ruwan tabarau mai lanƙwasa suna da tsayin daka mai kyau. Duk da cewa gilashin suna a wani nisa daga ido, an yi watsi da wannan a cikin wannan lissafin.
An san cewa:
Mai fama da matsalar ido kusa da wurin ido = nisan hoto (s') = -50 cm
Dole ne hoton ya kasance a gaban ruwan tabarau mai siffar convex domin a iya gani. Domin hoton yana gaban ruwan tabarau mai siffar convex, hoton yana kama da na kama-da-wane kuma yana da alamar rashin kyau.
Nisa ta karatu ta al'ada = nisan abu (s) = 25 cm
An tambaya: Ƙarfin gilashin ido
Amsa:
Tsawon maƙasudin ruwan tabarau mai lanƙwasa (f):
1/f = 1/s + 1/s'
1/f = 1/25 – 1/50 = 2/50 – 1/50
1/f = 1/50
f = 50 cm
f = mita 0,5 = mita 5/10 = mita 1/2
Tsawon haske na ruwan tabarau mai siffar convex yana da kyau saboda hasken yana ratsawa ta cikin wurin da ruwan tabarau mai siffar convex yake.
Ƙarfin gilashin da ke da convex (P) na gilashi:
P = 1 /f = 1: f
P = 1: 1/2
P = 1 x 2/1
P = 2/1
P = diopters 2
Ƙarfin gilashin convex na gilashin shine diopters 2.
Ƙarfin gilashin convex na gilashin yana da kyau saboda tsawon firikwensin gilashin convex yana da kyau.
Amsar da ta dace ita ce D.
6. Mutumin da ke fama da hyperopia zai iya karanta littafi a nisan santimita 125. Domin ya iya karatu a nisan santimita 25 na al'ada, dole ne mutumin ya sanya tabarau masu ƙarfin gilashin ido kamar….
A. 3 1/5 diopters
B. 2 ½ diopters
C. 1 diopters 3/5
D. 1 ¼ diopters
Tattaunawa
Mutumin yana da hangen nesa saboda kusancin idonsa shine 125 cm. Kusa da idon da aka saba gani shine 25 cm. Ana gyara hangen nesa ta amfani da ruwan tabarau mai lanƙwasa.
An san cewa:
Mai fama da matsalar ido kusa da wurin ido = nisan hoto (s') = -125 cm
Dole ne hoton ya kasance a gaban ruwan tabarau mai siffar convex domin a iya gani. Domin hoton yana gaban ruwan tabarau mai siffar convex, hoton yana kama da na kama-da-wane kuma yana da alamar rashin kyau.
Nisa ta karatu ta al'ada = nisan abu (s) = 25 cm
An tambaya: Ƙarfin gilashin ido
Amsa:
Tsawon maƙasudin ruwan tabarau mai lanƙwasa (f):
1/f = 1/s + 1/s'
1/f = 1/25 – 1/125
1/f = 5/125 – 1/125
1/f = 4/125
f = 125/4
f = 31,25 cm
f = mita 0,3125
Ƙarfin gilashin da ke da convex (P) na gilashi:
P = 1 /f
P = 1/0,3125
P = diopters 3,2
P = (3)(2/10) diopters
P = (3)(1/5) diopters
Ƙarfin gilashin da ke da lanƙwasa shine diopters 3,2 = diopters 3 1/5.
Amsar da ta dace ita ce A.
7. Mutum zai iya karatu sosai a nisan santimita 50. Domin ya iya karatu sosai a nisan santimita 30, ƙarfin gilashin ido da ake buƙata shine….
A. 1/3 diopter
B. 2/3 diopters
C. ¾ diopters
D. 4/3 diopters
Tattaunawa
An san cewa:
Mai fama da matsalar ido kusa da wurin ido = nisan hoto (s') = -50 cm
Dole ne hoton ya kasance a gaban ruwan tabarau mai siffar convex domin a iya gani. Domin hoton yana gaban ruwan tabarau mai siffar convex, hoton yana kama da na kama-da-wane kuma yana da alamar rashin kyau.
Nisan karatu = nisan abu (s) = 30 cm
An tambaya: Ƙarfin gilashin ido
Amsa:
Tsawon maƙasudin ruwan tabarau mai lanƙwasa (f):
1/f = 1/s + 1/s'
1/f = 1/30 – 1/50 = 5/150 – 3/150
1/f = 2/150
f = 150/2
f = 75 cm
f = mita 0,75 = mita 75/100 = mita 3/4
Ƙarfin gilashin da ke da convex (P) na gilashi:
P = 1 /f = 1: f
P = 1: 3/4
P = 1 x 4/3
P = 4/3 diopters
Ƙarfin gilashin da ke da convex shine 4/3 diopters.
Amsar da ta dace ita ce D.
8. Kalli hoton da ke ƙasa na samuwar inuwa a cikin ido!
Lalacewar ido da gilashin ido da ake amfani da su don tabbatar da cewa hoton ya yi daidai a kan retina sune…
Tattaunawa
Lalacewar ido: myopia ( near-sightness )
Ana iya mayar da hasken haske daidai kan retina idan aka sanya ruwan tabarau mai kauri ko mai karkacewa a gaban ido. Ruwan tabarau mai karkacewa yana taimakawa wajen yaɗa hasken ta yadda za a iya mayar da hankali kan retina daidai.
Amsar da ta dace ita ce C.
Tushen tambaya:
Tambayoyin Jarrabawar Ƙasa ta Kimiyya ta Makarantar Sakandare/Makarantar Sakandare ta Musulunci
