1.
What type of lens is a Magnifying Glass?
Correct Answer
A. Convex
Explanation
A magnifying glass is a type of lens that is convex. A convex lens is thicker in the middle and thinner at the edges, causing light rays to converge and focus at a point. This allows the magnifying glass to enlarge the size of an object when viewed through it. Concave lenses, on the other hand, are thinner in the middle and thicker at the edges, causing light rays to diverge. Parabolic lenses have a curved shape that can focus light to a single point, but they are not typically used in magnifying glasses. A plane lens is flat and does not have any curvature, so it does not have the ability to magnify.
2.
What is the bending of light rays due to a change in speed as the rays pass through a substance, called?
Correct Answer
B. Refraction
Explanation
Refraction is the bending of light rays due to a change in speed as the rays pass through a substance. This phenomenon occurs because light travels at different speeds in different mediums. When light enters a new medium at an angle, it changes direction, causing the rays to bend. This bending of light is responsible for various optical phenomena, such as the apparent bending of objects in water or the formation of rainbows. Reflection, diffusion, and diffraction are all different phenomena and do not involve the bending of light due to a change in speed.
3.
What type of lens is this?
Correct Answer
B. Concave
Explanation
A concave lens is a type of lens that is thinner at the center and thicker at the edges. It causes light rays to diverge or spread out, resulting in the image appearing smaller and upright. This type of lens is commonly used in correcting nearsightedness and in devices such as cameras and telescopes.
4.
Which type of mirror makes objects appear smaller, but the area of view larger?
Correct Answer
A. Convex
Explanation
A convex mirror makes objects appear smaller because it diverges light rays, causing them to spread out. This spreading out of light creates a wider field of view, making the area of view larger.
5.
What type of mirror is this?
Correct Answer
A. Convex
Explanation
This mirror is convex because it curves outward, causing light rays to diverge. Convex mirrors are commonly used in vehicles as side-view mirrors because they provide a wider field of view. They also make objects appear smaller and closer than they actually are.
6.
A convex lens will make an image appear ______ if the object is placed between the focal point and the lens.
Correct Answer
D. Larger and right side up
Explanation
When an object is placed between the focal point and a convex lens, the lens will create a virtual image that is larger than the object. This is because the light rays from the object diverge after passing through the lens, creating an image that appears larger. Additionally, the image will be right side up, meaning it will have the same orientation as the object. Therefore, the correct answer is "larger and right side up."
7.
Mirrors _____ light rays to make an image.
Correct Answer
A. Reflect
Explanation
Mirrors reflect light rays to make an image. When light hits a mirror, it bounces off the smooth surface of the mirror at the same angle it arrived. This process is called reflection. The reflected light rays then enter our eyes, allowing us to see the image formed by the mirror.
8.
A _____ mirror is like the side mirrors on a car. "Objects are closer than they appear".
Correct Answer
A. Convex
Explanation
A convex mirror is like the side mirrors on a car because it is curved outward, causing the reflection to appear smaller and farther away than they actually are. This distortion is similar to the warning on car mirrors that says "Objects are closer than they appear."
9.
An image formed with a lens that can be projected onto a screen is called a _____ image.
Correct Answer
B. Real
Explanation
A real image is formed by the actual intersection of light rays and can be projected onto a screen. This image is formed when light rays converge after passing through a lens, creating a focused and inverted image. It can be captured and recorded on a physical surface, such as a screen or photographic film. In contrast, a virtual image is formed by the apparent intersection of light rays and cannot be projected onto a screen.
10.
Is this a converging lens or a diverging lens?
Correct Answer
B. Diverging
Explanation
This answer indicates that the lens in question is a diverging lens. Diverging lenses are thinner in the middle and thicker at the edges. They cause parallel light rays to spread out or diverge. This is in contrast to converging lenses, which are thicker in the middle and thinner at the edges, and cause parallel light rays to converge at a focal point.
11.
The typical mirror you look in at home or in a restroom is a _____ mirror.
Correct Answer
D. Plane
Explanation
A plane mirror is a type of mirror that has a flat surface. When you look at yourself in a plane mirror, the reflection appears to be the same size and shape as the object being reflected. This is the type of mirror commonly found in homes and restrooms, where it is used for everyday tasks such as grooming and applying makeup.
12.
A convex mirror will always produce an image that is _____.
Correct Answer
C. Virtual , upright , smaller
Explanation
A convex mirror will always produce a virtual image that is upright and smaller compared to the object. This is because a convex mirror diverges light rays, causing them to spread out. As a result, the image formed appears to be behind the mirror and is smaller than the actual object. The image is also upright, meaning it is oriented in the same direction as the object.
13.
A concave lens will always produce a _____ image.
Correct Answer
A. Virtual , upright , smaller
Explanation
A concave lens is thinner at the center and thicker at the edges. When light passes through a concave lens, it diverges or spreads out. This causes the rays of light to appear to come from a point behind the lens, creating a virtual image. The image formed by a concave lens is always upright, meaning it is not flipped or inverted. Additionally, the image is smaller than the object because the light rays are spread out and do not converge to a single point. Therefore, the correct answer is "virtual, upright, smaller."
14.
What is the medical word for nearsightedness?
Correct Answer
A. Myopia
Explanation
Myopia is the correct answer because it is the medical term used to describe nearsightedness. It is a condition where a person can see objects up close clearly, but objects in the distance appear blurry. This occurs when the eyeball is too long or the cornea is too curved, causing light to focus in front of the retina instead of directly on it.
15.
What type lens is used to correct farsightedness ?
Correct Answer
A. Convex
Explanation
A convex lens is used to correct farsightedness because it is thicker in the middle and thinner at the edges. This shape helps to converge the incoming light rays, allowing them to focus properly on the retina, which is necessary for clear vision. Farsightedness occurs when the eyeball is too short or the cornea is not curved enough, causing light to focus behind the retina instead of on it. A convex lens helps to bring the image forward and onto the retina, correcting the farsightedness.
16.
A _____ uses 2 convex lenses to magnify an object and make a smaller object larger.
Correct Answer
B. Microscope
Explanation
A microscope uses 2 convex lenses to magnify an object and make a smaller object larger. The first lens, known as the objective lens, collects light from the object and forms a magnified real image. This image is then further magnified by the second lens, known as the eyepiece lens, which allows the viewer to see the enlarged image. The combination of these two lenses in a microscope enables scientists and researchers to observe tiny details and structures that are not visible to the naked eye.
17.
The image formed on the film in a camera and on the retina of your eye is _____.
Correct Answer
B. Upside down
Explanation
The image formed on the film in a camera and on the retina of your eye is upside down because light rays coming from an object cross each other before reaching the film or retina. This inversion of the image is due to the way light rays refract and converge in the lens of the camera or eye. However, our brain processes the visual information and interprets it as rightside up, allowing us to perceive the world correctly.
18.
A _____ uses large mirrors to bring distant objects into closer view.
Correct Answer
B. Telescope
Explanation
Telescopes use large mirrors to bring distant objects into closer view. They work by reflecting and focusing light from distant objects onto a smaller area, allowing us to see them in more detail. Microscopes, on the other hand, are used to magnify small objects that are too close to see clearly with the naked eye. Oscilloscopes are electronic devices used to measure and display waveforms, while kaleidoscopes are optical instruments that create beautiful patterns by reflecting and refracting light.
19.
If you are standing 4 feet from a plane mirror and looking into it, the image you see will be ______ feet away from the mirror on the other side.
Correct Answer
B. 4 feet
Explanation
When you stand 4 feet from a plane mirror and look into it, the image you see will appear to be 4 feet away from the mirror on the other side. This is because the image distance is equal to the object distance in a plane mirror. The image formed in a plane mirror is virtual, meaning it appears to be behind the mirror at the same distance as the object is in front of the mirror. Therefore, the correct answer is 4 feet.
20.
Name the mirror that is used as a flashlight and the lights of a car to create a beam of light.
Correct Answer
B. Concave
Explanation
A concave mirror is used as a flashlight and the lights of a car to create a beam of light. This is because a concave mirror has a curved surface that converges light rays towards a focal point, creating a concentrated beam of light.