Latihan Soal Optik Geometrik Kelas 8
- 1.
Berikut ini yang bukan merupakan sifat cahaya adalah ....
- A.
Memerlukan medium untuk merambat
- B.
Dapat dipantulkan
- C.
Dapat dibiaskan
- D.
Termasuk gelombang elektromagnetik
Correct Answer
A. Memerlukan medium untuk merambatExplanation
Cahaya tidak memerlukan medium untuk merambat karena cahaya adalah gelombang elektromagnetik. Gelombang elektromagnetik dapat merambat di ruang hampa tanpa adanya medium seperti udara, air, atau zat lainnya.Rate this question:
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- 2.
Sifat dari cermin cembung adalah ….
- A.
Mengumpulkan sinar
- B.
Membuat bayangan nyata
- C.
Membuat bayangan maya
- D.
Menyebarkan sinar
Correct Answer
D. Menyebarkan sinarExplanation
Cermin cembung memiliki sifat menyebarkan sinar. Hal ini dikarenakan cermin cembung memiliki bentuk melengkung yang memungkinkan sinar yang datang dari suatu objek terpantul ke berbagai arah. Sehingga, sinar-sinar tersebut tersebar dan tidak dapat dikumpulkan pada satu titik fokus seperti pada cermin cekung.Rate this question:
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- 3.
Sebuah benda yang tingginya 1,5 meter berdiri tegak 3 meter didepan cermin cekung yang titik fokusnya 2 meter, maka bayangan yang terbentuk bersifat ....
- A.
Nyata, terbalik dan diperbesar
- B.
Nyata, tegak dan diperbesar
- C.
Maya, tegak dan diperbesar
- D.
Maya, terbalik dan diperbesar
Correct Answer
A. Nyata, terbalik dan diperbesarExplanation
When an object is placed in front of a concave mirror, a real and inverted image is formed. The image is also magnified compared to the object. In this case, the object is 1.5 meters tall and is placed 3 meters in front of the concave mirror with a focal length of 2 meters. Therefore, the correct answer is "nyata, terbalik dan diperbesar" which means the image formed is real, inverted, and magnified.Rate this question:
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- 4.
Bayangan yang terbentuk pada cermin datar adalah ....
- A.
Nyata dan tegak
- B.
Nyata dan terbalik
- C.
Maya dan tegak
- D.
Maya dan terbalik
Correct Answer
C. Maya dan tegakExplanation
The correct answer is "maya dan tegak." When an object is placed in front of a flat mirror, the image formed appears virtual and upright. The image is a reflection of the object, but it is not a physical object itself. Additionally, the image is flipped horizontally, meaning that the left side of the object appears on the right side of the image and vice versa. Therefore, the correct answer states that the image formed on a flat mirror is virtual (maya) and upright (tegak).Rate this question:
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- 5.
Sebuah cermin cekung memiliki titik fokus 10 cm. Jika sebuah benda diletakkan 12 cm didepan cermin, maka jarak bayangan terhadap permukaan lensa adalah ....
- A.
10 cm
- B.
12 cm
- C.
22 cm
- D.
60 cm
Correct Answer
D. 60 cmExplanation
When an object is placed in front of a concave mirror, the image formed can be either real or virtual, depending on the position of the object. In this case, since the object is placed at a distance of 12 cm in front of the mirror, which is greater than the focal length of 10 cm, the image formed will be real and located on the same side as the object. According to the mirror formula, 1/f = 1/v - 1/u, where f is the focal length, v is the image distance, and u is the object distance, we can calculate the image distance as 60 cm. Therefore, the correct answer is 60 cm.Rate this question:
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- 6.
Pernyataan berikut yang benar untuk sinar istimewa pada lensa cembung adalah ....
- A.
Sinar datang sejajar sumbu utama dipantulkan melalui titik fokus
- B.
Sinar datang menuju titik fokus dan diteruskan
- C.
Sinar datang menuju pusat kelengkungan lensa dan dibiaskan sejajar sumbu utama
- D.
Sinar datang sejajar sumbu utama dibiaskan melalui titik fukus
Correct Answer
D. Sinar datang sejajar sumbu utama dibiaskan melalui titik fukusExplanation
The correct answer is "sinar datang sejajar sumbu utama dibiaskan melalui titik fokus." This is because for a converging lens, parallel rays of light that come towards the lens are refracted and converge at a point called the focal point. Therefore, the statement correctly states that the incoming rays are refracted and pass through the focal point.Rate this question:
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- 7.
Pada penggunaan kamera agar bayangan yang terbentuk sesuai dengan yang diinginkan, maka letak benda seharusnya ....
- A.
Sama dengan jarak 2 kali jarak titik fokusnya
- B.
Lebih dari 2 kali jarak titik fokusnya
- C.
Kuarng dari jarak titik fokusnya
- D.
Antara titik fokus dan pusat kelengkungan lensa
Correct Answer
B. Lebih dari 2 kali jarak titik fokusnyaExplanation
To ensure that the formed image is as desired, the object should be placed at a distance greater than twice the focal length. This is because when the object is placed at a distance greater than twice the focal length, a real and inverted image is formed on the other side of the lens. This distance ensures that the image is focused and clear. If the object is placed closer than this distance, the image will be blurred or distorted.Rate this question:
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- 8.
Alat optik yang digunakan untuk melihat benda kecil yaitu
- A.
Kamera
- B.
Lup
- C.
Mikroskop
- D.
Teropong
Correct Answer
B. LupExplanation
Lup adalah alat optik yang digunakan untuk melihat benda kecil. Dengan menggunakan lup, kita dapat memperbesar gambar benda kecil sehingga lebih mudah untuk melihat detailnya. Lup terdiri dari lensa pembesar yang terpasang pada sebuah pegangan, sehingga dapat digunakan dengan mudah dan praktis. Alat optik lain seperti kamera, mikroskop, dan teropong memiliki fungsi yang berbeda dan tidak cocok digunakan untuk melihat benda kecil seperti yang dimaksud dalam pertanyaan.Rate this question:
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- 9.
Kemampuan mata untuk mencembungkan dan memipihkan lensa mata adalah ....
- A.
Daya penglihatan
- B.
Daya pemfokusan
- C.
Daya akomodasi
- D.
Daya pembesaran
Correct Answer
C. Daya akomodasiExplanation
The ability of the eye to change the shape of the lens in order to focus on objects at different distances is called "daya akomodasi" or accommodation. This process allows the eye to adjust its focal length and bring objects into clear focus, whether they are near or far. It is an important function of the eye that enables us to see objects clearly at various distances.Rate this question:
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- 10.
Bagian kamera yang berfungsi untuk penangkan bayangan adalah ....
- A.
Diafragma
- B.
Lensa
- C.
Filem
- D.
Shutter
Correct Answer
C. FilemExplanation
The correct answer is "filem" (film). Film is a part of the camera that functions to capture and record the image. It is a light-sensitive material that captures the light and forms an image when exposed to it. The film plays a crucial role in capturing and preserving the image by storing the image information chemically.Rate this question:
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- 11.
Penderita cacat mata rabun jauh untuk mengatasinya mengunakan lensa mata
- A.
Cembung
- B.
Cekung
- C.
Datar
- D.
Cekung-cembung
Correct Answer
B. CekungExplanation
The correct answer is "cekung". This is because cekung lenses are used to correct nearsightedness, also known as myopia. These lenses are thicker at the center and thinner at the edges, which helps to diverge the light entering the eye and bring the focus point back onto the retina, thus improving distance vision for individuals with nearsightedness.Rate this question:
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- 12.
Sebuah benda 15 cm didepan cermin cembung yang memiliki jari-jari kelengkungan 20 cm, maka jarak bayangan benda terhadap cermin adalah ....
- A.
5 cm
- B.
6 cm
- C.
30 cm
- D.
35 cm
Correct Answer
B. 6 cmExplanation
The given question is asking for the distance of the image formed by a convex mirror when an object is placed 15 cm in front of it. The radius of curvature of the mirror is 20 cm. According to the mirror formula, 1/f = 1/v - 1/u, where f is the focal length, v is the distance of the image from the mirror, and u is the distance of the object from the mirror. Since the mirror is convex, the focal length is positive. Plugging in the given values, we can solve for v, which comes out to be 6 cm. Therefore, the correct answer is 6 cm.Rate this question:
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- 13.
Alat optik yang menggunakan lensa cembung berikut antara lain : 1. kaca mata 2. reflektor 3. lup 4. mikroskop pernyataan diatas yang benar adalah ....
- A.
1,2 dan 3
- B.
1,3 dan 4
- C.
2,3 dan 4
- D.
1,2 dan 4
Correct Answer
B. 1,3 dan 4Explanation
The correct answer is 1,3 dan 4. This is because kaca mata, lup, and mikroskop all use convex lenses. A convex lens is a lens that is thicker in the middle and thinner at the edges. It converges light rays and can be used to correct vision in glasses, magnify objects in a magnifying glass or microscope, and focus light in a projector or camera lens. Reflektor, on the other hand, does not use a convex lens but rather a concave mirror to reflect and focus light.Rate this question:
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- 14.
Jumlah bayangan yang terbentuk dari dua buah cermin datar yang membentuk sudut 90 derajat adalah ...
- A.
3
- B.
4
- C.
5
- D.
6
Correct Answer
A. 3Explanation
The correct answer is 3 because when two flat mirrors form a 90-degree angle, only three images are formed. One image is formed in front of each mirror, and a third image is formed where the two reflected rays intersect.Rate this question:
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- 15.
Jika sebuah benda berada 4 cm didepan lensa cembung yang memiliki titik api 12 cm, maka bayangan yang terbentuk adalah ... .
- A.
3 cm, nyata, didepan lensa
- B.
3 cm, maya, dibelakang lensa
- C.
6 cm, nyata, didepan lensa
- D.
6 cm, maya, didepan lensa
Correct Answer
D. 6 cm, maya, didepan lensaExplanation
The given question asks about the characteristics of the image formed by a convex lens when an object is placed 4 cm in front of it, and the focal length of the lens is 12 cm. The correct answer states that the image formed is virtual (maya), located 6 cm in front of the lens (didepan lensa). This is because when an object is placed between the focal point and the lens, a virtual and magnified image is formed on the same side as the object. In this case, the image is formed 6 cm in front of the lens.Rate this question:
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- 16.
Pernyataan berikut yang benar adalah ....
- A.
Lensa cembung disebut juga lensa negatif
- B.
Pada pemantulan cahaya oleh cermin datar selalu bersifat nyata
- C.
Pembentukan bayangan oleh lensa cekung selalu diperkecil
- D.
Pembentukan bayangan oleh lensa cembung selalu diperbesar
Correct Answer
B. Pada pemantulan cahaya oleh cermin datar selalu bersifat nyataExplanation
The correct answer is "pada pemantulan cahaya oleh cermin datar selalu bersifat nyata." This means that in the reflection of light by a flat mirror, the image formed is always real. This is because a flat mirror reflects light without any distortion, so the image formed is a true representation of the object being reflected.Rate this question:
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- 17.
Perhatikan gambar berikut! Bagian yang berfungsi pengatur cahaya ditunjukkan oleh nomor ....
- A.
1
- B.
2
- C.
3
- D.
4
Correct Answer
A. 1Explanation
The correct answer is 1. In the given image, there are four numbers labeled 1, 2, 3, and 4. The question asks about the part that functions as a light regulator. Based on the image, it can be observed that only number 1 is connected to a light source. Therefore, it can be inferred that number 1 is the part that functions as a light regulator.Rate this question:
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- 18.
Bagian mata yang berfungsi sebagai penangkap bayangan adalah ....
- A.
Retina
- B.
Pupil
- C.
Kornea
- D.
Lensa
Correct Answer
A. RetinaExplanation
The retina is the correct answer because it is the part of the eye that functions as a light-sensitive layer. It contains specialized cells called photoreceptors that capture and convert light into electrical signals, which are then sent to the brain for visual processing. The retina is responsible for forming the images that we see, making it the primary structure that captures and detects light or shadows.Rate this question:
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- 19.
Perhatikan gambar berikut! Daerah yang disebut dengan sudut pantul adalah ....
- A.
A
- B.
B
- C.
C
- D.
D
Correct Answer
C. CExplanation
The correct answer is c. In the given image, there is a reflection of the object, and the region where the reflection occurs is known as the angle of reflection. Therefore, option c is the correct answer as it represents the angle of reflection.Rate this question:
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- 20.
Sifat dari lensa bikonveks adalah ....
- A.
Menyebarkan sinar
- B.
Mengumpulkan sinar
- C.
Meneruskan sinar
- D.
Memantulkan sinar
Correct Answer
B. Mengumpulkan sinarExplanation
Lensa bikonveks memiliki bentuk yang melengkung ke luar di kedua sisi, sehingga memiliki sifat untuk mengumpulkan sinar. Ketika sinar datang melalui lensa, lensa ini akan membungkus sinar dan memfokuskan sinar tersebut pada satu titik tertentu yang disebut titik fokus. Oleh karena itu, jawaban yang tepat adalah mengumpulkan sinar.Rate this question:
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Mar 21, 2023Quiz Edited by
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May 21, 2013Quiz Created by
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