3 Tusaalooyin su'aalo ah oo ku saabsan muraayadaha indhaha
1. Ka soo qaad saaxiibkaa inuu xidho muraayado leh muraayado leh awood dhan -2 diopters. Muraayadaha indhaha guud ahaan 2 cm u jirta isha.
(a) Saaxiibkaa wuxuu haystaa muraayado muraayad qaloocan ama muraayad qaloocan ?
(b) Waa maxay dhererka diiradda ee muraayadda?
(c) Indhaha saaxiibkaa aragti fog ama aragti fog Haddii aad tahay qof aan arag fog lahayn, waa maxay masaafada ugu fog ee indhahaagu arki karaan? Haddii aad tahay qof aan arag fog lahayn, waa maxay masaafada ugu dhow ee ay ishaadu aragto?
Dood
Waa la garanayaa :
Awoodda muraayadda (P) = -2 diopters
Jawab :
(a) Muraayad qaloocan mise muraayad qaloocan?
Awoodda muraayadda waa taban, sidaa darteed muraayadda la isticmaalay waa muraayad taban, oo loo yaqaan muraayad concave ah, oo sidoo kale loo yaqaan muraayad kala duwan.
(b) Waa maxay dhererka diiradda ee muraayadda?
P = 1/f
-2 = 1/f
f = 1/-2 = -0,5 mitir = -50 cm
Dhererka diiradda ee muraayadda qaloocan waa 50 cm.
(c) Saaxiibkaa ma aragti fog baa mise aragti fog baa?
Haddii muraayadda la isticmaalay ay tahay muraayad qaloocan markaa indhaha saaxiibkaa way muuqan doonaan aragti fogHaddii uu yahay qof aan arag fog lahayn, waa maxay masaafada ugu fog ee ay indhaha saaxiibkaa arki karaan?
Meesha ugu fog ee isha caadiga ah waa xad la'aan, halka saaxiibkaa uu yahay mid fog, sidaa darteed masaafada ugu fog ee isha saaxiibkaa ay aragto waa mid ka yar xad la'aan. Si isha saaxiibkaa ay u awoodo inay walxaha ku aragto masaafo aan dhammaad lahayn sida isha caadiga ah, muraayadda muraayadda indhaha waa inay sameysaa sawir shayga ah masaafo x cm ah oo ku taal muraayadda horteeda. Sawirku wuxuu ku yaal hortiisa muraayadda muraayadda indhaha sidaas darteed sawirku waa mid toosan oo casri ah (isbarbardhig sharraxaadda mawduuca). sawirka muraayadda qaloocan)Maadaama sawirku yahay mid casri ah, masaafada sawirka (yada) waa taban. Sidoo kale, dhererka diiradda muraayadda waa taban sababtoo ah muraayadaha ayaa leh muraayad qaloocan.
-1/s' = 1/f – 1/s
-1/s' = -1/50 – 1/~ = -1/50 – 0
-1/s' = -1/50
s' = 50 cm
Masaafada sawirka ee ka horraysa muraayadda indhaha waa 50 cm. Muraayadaha indhaha waxay 2 cm u jiraan indhaha hortiisa sidaa darteed masaafada sawirka ee ka horraysa isha waa 50 cm + 2 cm = 52 cm. 52 cm waa masaafada ugu fog ee ay arki karto isha indhaha ee dhibaatada kore. Masaafada ugu fog ee isha caadiga ahi arki karto waa xad la'aan.
2. Ka soo qaad in saaxiibtaa ay xirato muraayado leh 4 muraayadood oo diopter ah. Muraayadaha guud ahaan waxay 2 cm ka horreeyaan indhaheeda.
(a) Muraayadaha saaxiibkaa ma isticmaalaan muraayadaha indhaha ee wareegsan ama muraayadaha indhaha ee wareegsan?
(b) Waa maxay dhererka diiradda ee muraayadda?
(c) Saaxiibkaa ma aragti fog baa mise aragti fog baa? Haddii aad aragti fog tahay, waa maxay masaafada ugu fog ee indhahaagu arki karaan? Haddii aad aragti fog leedahay, waa maxay masaafada ugu dhow ee ay ishu arki karto?
Dood
Waa la garanayaa :
Awoodda muraayadda (P) = 4 diopters
Jawab :
(a) Muraayad qaloocan mise muraayad qaloocan?
Awoodda muraayadda waa mid togan, sidaa darteed muraayadda la isticmaalay waa muraayad togan, oo loo yaqaan muraayad convex ah, oo sidoo kale loo yaqaan muraayad isku dhafan.
(b) Waa maxay dhererka diiradda ee muraayadda?
P = 1/f
4 = 1/f
f = 1/4 = 0,25 mitir = 25 cm
Dhererka diiradda ee muraayadda qaloocan waa 25 cm.
(c) Saaxiibkaa ma aragti fog baa mise aragti fog baa?
Haddii muraayadda la isticmaalay ay tahay muraayad qaloocan markaa indhaha saaxiibkaa ayaa noqon doona aragti fogHaddii aad tahay qof aan arag fog lahayn, waa maxay masaafada ugu dhow ee ishu arki karto?
Barta u dhow isha caadiga ah waa 25 cm. Si indhaha saaxiibkaa ay u awoodaan inay arkaan shay 25 cm u jira sida isha caadiga ah, muraayadda muraayadda waa inay sameysaa sawir masaafad x cm ah oo ku taal muraayadda horteeda. Muraayadda muraayadda indhaha waa 2 cm horteeda isha, sidaa darteed masaafada shayga ee horteeda muraayadda waa 25 cm – 2 cm = 23 cm. Sawirku wuxuu ku yaal horteeda muraayadda muraayadda indhaha, sidaa darteed sawirku waa mid toosan oo casri ah (isbarbardhig sharraxaadda mawduuca. sawirka muraayadda qaloocan)Sawirku waa mid casri ah, sidaas darteed masaafada sawirku waxay leedahay calaamad taban.
-1/s' = 1/f – 1/s
-1/s' = 1/25 – 1/23 = 23/575 – 25/575 = -2/575
-s' = 575/-2 = -287,5 cm = -2,875 mitir
s' = 287,5 cm = 2,875 mitir
Masaafada sawirka ee ka horraysa muraayadda indhaha waa 287,5 cm. Masaafada sawirka ee ka horraysa isha waa 287,5 cm + 2 cm = 289,5 cm. 289,5 cm waa masaafada ugu dhow ee isha aragga dhow ku arki karto dhibaatada kor ku xusan. Masaafada ugu dhow ee isha caadiga ahi arki karto waa 25 cm.
3. Qofku si cad ayuu wax u akhrin karaa masaafad dhan 50 cm. Si uu si cad wax ugu akhriyo masaafad dhan 30 cm, awoodda muraayadaha indhaha ee loo baahan yahay waa…
A. 1/3 diopter
B. 2/3 diopters
C. 3/4 diopters
D. 4/3 diopters
Dood
Qofku wuxuu la ildaran yahay aragga dhow, muraayadaha loo isticmaalo in lagu caadiyeeyo indhaha dhow waa muraayadaha wareegsan ama muraayadaha isku dhafan ama muraayadaha togan.
Si shay loogu arko masaafad dhan 30 cm oo horta isha ah, muraayaddu waa inay sawir ka sameysaa masaafad dhan 50 cm oo horta isha ah. Sawirku wuxuu horta muraayadda ka yaallaa, sidaas darteed sawirku waa mid toosan oo casri ah.
Waa la ogyahay in:
Masaafada shayga (yada) = 30 cm
Masaafada sawirka (yada) = -50 cm (taban sababtoo ah waa mid casri ah)
Su'aal: Awoodda muraayadda (P)
Jawaab:
Dhererka diiradda (f) ee muraayadda:
1/f = 1/s + 1/s'
1/f = 1/30 + 1/-50
1/f = 5/150 – 3/150
1/f = 2/150
f = 150/2 = 75 cm = 0,75 mitir = 75/100 mitir
Dhererka diiradda togan macnaheedu waa in muraayadda la isticmaalay ay tahay muraayad wareegsan.
Awoodda muraayadda:
P = 1/f
P = 1: 75/100 = 1 x 100/75
P = 100/75 (u qaybi 25)
P = 4/3 diopters
Jawaabta saxda ah waa D.
Su'aalo ku saabsan Muraayadaha Indhaha
1. Qof ayaa isticmaala kacamata waxay leedahay awood dhan -2,5 diopters. Haddii muraayadda muraayadda indhaha ay guud ahaan 2 cm u jirto isha, go'aami:
(a) Muraayadaha indhaha ma isticmaalaan muraayadaha indhaha ee wareegsan ama kuwa wareegsan?
(b) Waa maxay dhererka diiradda ee muraayadda muraayadda indhaha?
(c) Indhaha qofka ma aragti fog baa mise aragti fog baa? Haddii aad aragti fog tahay, waa maxay masaafada ugu fog ee indhahaagu arki karaan? Haddii aad aragti fog tahay, waa maxay masaafada ugu dhow ee ay ishu arki karto?
Furaha jawaabta:
a = muraayad kala duwan = muraayad taban = muraayad….
b = 40cm
c = Arbacada Dheer. Masaafada ugu fog = 42 cm
2. Ka soo qaad in saaxiibkaa hore uu isticmaalo kacamata oo leh awood 4,5 diopters ah 🙂. Haddii muraayadda muraayadda indhaha ay guud ahaan 2 cm u jirto isha, go'aami:
(a) Muraayadaha saaxiibkaa hore ma isticmaalay muraayado wareegsan ama muraayado wareegsan?
(b) Waa maxay dhererka diiradda ee muraayadda muraayadda indhaha?
(c) Saaxiibkii hore ma aragti fog ayuu lahaa mise aragti fog buu lahaa? Haddii aragti fog uu leeyahay, masaafada ugu fog ee ishu arki karto waa maxay? Haddii aragti fog uu leeyahay, waa maxay masaafada ugu dhow ee ishu arki karto?
Furaha jawaabta:
a = muraayad isku soo ururaysa = muraayad togan = muraayad….
b = 22,2cm
c = Aragti dhow. Masaafada ugu dhow = 13,3 cm
