19. 'n Gebou wat 30 m hoog is word afgeneem met'n kamera met 'n 50 mm brandpuntafstand lens. Hoe hoog is die beeld op die film indien die gebou 100 m weg is? (3) A building 30 m tall is being photographed with a camera with a lens of focal length 50 mm. How tall is the image on the film if the building is 100 m away? (3) A. 1,0 mm B. 3,0 mm C. 10 mm D. 15 mm E. 30 mm 20. 'n Voorwerp wat 4.0 cm hoog is, word 60 cm voor 'n divergerende lens met brandpuntafstand 30 cm geplans. Watter inskrywing in die tabel is korrek? (3) A 4,0 cm high object is placed 60 cm in front of a diverging lens of focal length 30 cm. Which entry in the table below is correct? (3) Beeldposisie vanaf lens beeldgrootte Image position from lens image height A. 20 cm voor / 20 cm in front 1,3 cm B. 20 cm agler / 20 cm behind 1,3 cm C. 30 cm voor / 30 cm in front 4,0 cm D. 60 cm voor / 60 cm in front 4,0 cm E. 60 cm agler / 60 cm behind 4,0 cm 21. Wanneer'n voorwerp voor 'n konvekslens met brandpuntalistand 12 cm geplass word, vorm 'n virtuele beeld 36 cm vanaf die lens. Die lineere afstand tussen die voorwerp en die beeld is (3) When an object is placed in front of a convex lens of focal lens 12 cm, a virtual image is formed 36 cm from the lens. The linear distance between the object and the image is (3) A. 9,0 cm B. 18 cm C. 27 cm D. 36 cm E. 54 cm 22. Wanneer, in die vorige vraag, die konvekslens by dieselfde posisie meth konkaaflens, ook met brandpuntafstand 12 cm, vervang word en die voorwerp op dieselfde plek gehou word, is die nuwe beeld (3) When, in the previous question, the convex lens is replaced at the same position by a concave lens, also with focal length 12 cm and the object kept at the same position, the new image is (3) 36 cm voor die konkaaflens. A. 36 cm in front of the concave lens. B. 36 cm agter die konkaaflens. 36 cm behind the concave lens. C. 7,2 cm voor die konkaaflens. 7,2 cm in front of the concave lens. D. 5,1 cm agler die konkaaflens. 5,1 cm behind the concave lens. E. 5,1 cm voor die konkaaflens. 5,1 cm in front of of the concave lens. 23. 'n Persoon se bysiendheid (myopia) word gekorrigeer deur lense met sterkie -5,00 D. Sonder sy bril was sy nabypunt 12,5 cm. Met sy bril, wat is sy nabypunt nou? Aanvaar die brillense is bale naby aan sy oe. (3) A person's nearsightedness (myopia) is corrected by lenses with a power of -5,00 D. Without his glasses, his near point was 12,5 cm. With his glasses on, what is his near point? Assume the lenses are very close to his eyes. (3) A. 7,5 cm B. 13,0 cm C. 17,5 cm D. 20,0 cm 33,0 cm