Latihan Soal ALAT Optik

A person with myopia has difficulty seeing objects that are far away. The doctor suggests wearing glasses with a strength of -½ diopter, which will help correct the nearsightedness. The strength of the glasses indicates how much the light is bent to focus properly on the retina. By wearing glasses with -½ diopter, the person will be able to see objects that are 200 cm away, which is the correct answer.

Lisa tidak dapat melihat benda pada jarak lebih dari 1 m, yang menunjukkan bahwa ia mengalami masalah penglihatan jauh. Untuk membaca dengan normal, Lisa membutuhkan kacamata dengan daya sebesar -1 dioptri. Daya negatif menunjukkan bahwa kacamata tersebut digunakan untuk memperbaiki penglihatan jauh.

The correct answer is retina. Film in a camera functions similarly to the retina in the eye. The retina is the part of the eye that receives light and converts it into electrical signals that are sent to the brain, allowing us to see. Similarly, in a camera, the film captures the light that enters the camera and records the image that is formed, which can then be developed into a photograph.

Presbiopia is a condition where the eye loses its ability to focus on nearby objects, typically occurring with age. Rangkap lenses have multiple focal points, allowing the wearer to see clearly at different distances. This makes rangkap lenses a suitable solution for presbiopia as they can provide clear vision for both near and far objects.

The correct answer is 2,5 dioptri. The question states that the near point of a student's eye is 120 cm in front of the eye. To see an object clearly at a distance of 30 cm in front of the eye, the lens power needed can be calculated using the formula: Lens power (in diopters) = 1 / focal length (in meters). The focal length can be calculated as follows: 1 / focal length = 1 / object distance - 1 / image distance. Plugging in the values, we get: 1 / focal length = 1 / 0.3 - 1 / 0.12. Solving this equation gives us a focal length of 0.1 m, which corresponds to a lens power of 10 diopters. However, since the question asks for the lens power of glasses, which are placed in front of the eye, the sign of the lens power should be negative. Therefore, the correct answer is -10 dioptri, which is equivalent to -2.5 dioptri.

The correct answer is "nyata, tegak, diperbesar". This means that the shadow formed by the magnifying glass is real, upright, and enlarged.

The total magnification of a microscope is calculated by multiplying the magnification of the objective lens by the magnification of the eyepiece. In this case, the magnification of the objective lens is 4 mm and the magnification of the eyepiece is 5 cm. To convert the units, we need to convert 4 mm to cm, which is 0.4 cm. Therefore, the total magnification is 0.4 cm x 5 cm = 2 cm. Since the answer choices are given in terms of "kali" (times), we need to multiply the magnification by 100 to get the final answer of 200 kali.

The formation of an image on a magnifying glass for an unaccommodated eye occurs when the lens of the eye is unable to adjust its shape to focus on nearby objects. This causes the light rays to converge at a point in front of the retina, resulting in a blurred image. Option 2 is the correct answer because it implies that the eye is not able to accommodate or adjust its focus properly.

The correct answer is "Lensa objektif = bayangan nyata dan diperbesar; lensa okuler = bayangan maya dan diperbesar." This means that the objective lens of the microscope forms a real and enlarged image, while the eyepiece lens forms a virtual and enlarged image. This is the correct configuration for a microscope, as the objective lens is responsible for magnifying the specimen and forming a real image, which is then further magnified by the eyepiece lens to create a virtual image that can be viewed by the observer.

The final image formed by a stage telescope is real and upright.