Light Important Questions and Answers
Students who want to score good marks in class 8 Science subject examinations, here are givenimportant questions and answers about lightfor their preparation . With the information of these important questions and answers, you can prepare well for class 10 examination. Questions and answers related to light are taught to us under Science. For the students who are looking for information related to the lesson light, in this post, important questions related to light and their answers have been given which have been asked in the exam earlier also.
Question 1: Can anyone see in the dark?
Answer: No.
Question 2: What do we need to see?
Answer: Light.
Question 3: Name two luminous objects.
Answer: (i) The Sun, (ii) Electric bulb.
Question 4: Is the moon a luminous or non-luminous object?
Answer: Non-luminous object.
Question 5: Where do we see a reflection?
Answer: In a mirror.
Question 6: What surfaces can form a mirror?
Answer: Any polished or shiny surface.
Question 7: If you stand in front of a mirror and see your reflection, what is the distance between you and your reflection?
Answer: The distance between the object and the mirror equals the distance between the reflection and the mirror. Thus, we are at double the distance from our reflection.
Question 8: When a ray of light falls perpendicular to the mirror, what is the angle of incidence?
Answer: Zero.
Question 9: Name two objects that split white light into multiple colors.
Answer: Water bubbles, CD surface, prism.
Question 10: Name the seven colors of light.
Answer: Red, orange, yellow, green, blue, indigo, violet.
Question 11: What is a natural example of the seven colors?
Answer: Rainbow.
Question 12: What is the function of the sclera (white covering) in the human eye?
Answer: The sclera gives shape to the eye and protects the internal parts from damage.
Question 13: What is the function of the ciliary muscle in the human eye?
Answer: The ciliary muscle holds the eye lens in place and helps in changing its focus.
Question 14: Is the focus of the eye lens fixed?
Answer: No. The focus of the human eye lens is not fixed; it changes due to the ciliary muscle.
Question 15: What is the function of rods in the human eye?
Answer: Rods are sensitive to light intensity. They are more stimulated by higher light intensity.
Question 16: What are cones?
Answer: Cones on the retina are color sensors. If cones are fewer or absent, a person suffers from color blindness.
Question 17: What is the main cause of color blindness?
Answer: The main cause of color blindness is having fewer or no cones.
Question 18: How do cats and bats see at night?
Answer: Their retinas have a high number of rods, enabling them to see even in very dim light.
Question 19: At what rate do images change on a movie screen?
Answer: 25 frames/second or more.
Question 20: What are the light-sensitive components on the retina?
Answer: Cones and rods.
Question 21: What are luminous and non-luminous objects? Give examples.
Answer: Luminous objects emit their own light, like the Sun, stars, fire, and radium. Non-luminous objects do not emit their own light but shine due to luminous objects, such as the Moon, Earth, other planets, and objects in a room.
Question 22: How do we see objects?
Answer: When light from a source falls on an object, it is reflected by the object. This reflected light enters the eyes, forming an image of the object in the eyes, which makes the object visible.
Question 23: What conditions are necessary to see an object?
Answer: Three conditions are necessary to see an object: (1) light source, (2) object, (3) sight.
Question 24: What is a virtual image? Give a situation where a virtual image is formed.
Answer: A virtual image is formed when light rays do not actually meet but appear to meet when reflected or refracted. It cannot be captured on a screen. A virtual image always forms in a mirror.
Question 25: What is meant by lateral inversion?
Answer: Lateral inversion refers to the phenomenon where the right side of an object appears as the left side and the left side as the right side in its image in a plane mirror.
Question 26: What is the dispersion of light?
Answer: Dispersion of light occurs when white light passes through a prism and splits into its constituent colors. This phenomenon of splitting white light into its constituent colors is called dispersion.
Question 27: Why does white light split into seven colors when passing through a prism?
Answer: Different colors of light waves pass through air easily but change their speed and direction according to the angle of the prism when passing through it. The amount of deviation varies for each color, resulting in them traveling in different paths and forming a spectrum.
Question 28: What is myopia (nearsightedness)?
Answer: Myopia is a condition where the focal length of the eye lens is shorter, causing the image of distant objects to form in front of the retina. This means a person cannot see distant objects clearly. This defect is called nearsightedness.
Question 29: What is hypermetropia (farsightedness)?
Answer: Hypermetropia is a condition where, due to aging, the muscles of the eye lens weaken and cannot control the curvature of the lens. The image of nearby objects forms behind the retina, meaning a person cannot see nearby objects clearly. This defect is called farsightedness.
In this post we have given you Light Class 8 Science Question Answer, Questions related to light, PDF download of class 8 science chapter 16 question answer in Hindi, Questions and Answers of Class 8 Science Chapter 16, Class 8 Science Chapter 16 Notes, Chapter 16 Questions and Answers about Light, complete information has been given about light. If you have any question or suggestion regarding this, then definitely ask us by commenting below and if you find this information useful, then definitely share it with your friends.