NCERT Solutions for Class 8 Science Chapter 16
NCERT Class 8 Science Chapter 16 is Light. This chapter focuses on the electromagnetic radiations that may be recognized by human vision and are referred to as visible light. The electromagnetic spectrum is quite vast, ranging from low-energy radio waves with wavelengths in meters to high-energy gamma-ray with a wavelength of fewer than 1×10-11 meters. Magnetic fields are fluctuated by electromagnetic radiations, which transmit energy at the speed of light. A stream of photons and massless energy packets are other terms for light. The photon is the smallest unit of energy that can be transferred.
Students may find it tricky to understand the concepts when it comes to a chapter such as light. However, it becomes easier to comprehend the chapter if the students refer to Class 8 Science Chapter 16 Solutions by Extramarks. This is because class 8, Chapter 16 NCERT Solutions, is developed exclusively by Extramarks experts, keeping in mind all the needs of the students.
Extramarks Class 8 Science Chapter 16 benefits the students in grasping all minor and significant concepts of the chapter. Apart from NCERT Solutions for Class 8 Science Chapter 16- Light, NCERT Solutions of other chapters and subjects, Additional Questions, Sample Papers, Revision Notes, CBSE past years’ question papers, and a lot more can be found on the Extramarks website.
Key Topics Covered in NCERT Solutions for Class 8 Science Chapter 16
Given is the list below of the key topics that are covered in NCERT Solutions for Class 8 Chapter 16 Science:
| Introduction to Light |
| Laws of Reflection |
| Types of Reflection |
| Difference between Real and Virtual Image |
| Dispersion |
| Human Eye |
| The Braille System |
Let us look at Extramarks’ in-depth information on each subtopic in NCERT Solutions for Class 8 Science Chapter 16- Light.
Introduction to Light
Extramarks NCERT Solutions for Class 8 Science Chapter 16 briefly introduces light in this section.
The world as we know is mainly understood through our senses, with sight being one of the most crucial senses. Objects can only be seen when light falls onto the object and is reflected back to our eyes to form an image in our brain.. The following are some key terms linked to light:
The energy that allows us to see is known as light. A source of light, such as the Sun, emits light. The term generally refers to visible light i.e visible to the naked eye and responsible for our ability to see.
How do we see objects?
When light falls on an object from the source of light (mainly, sun) it gets reflected in all directions. The reflected light then reaches our eyes and our brain perceives the image of that object.
Laws of Reflection
Light is reflected off of many surfaces. Any highly polished or gleaming surface can work as a mirror and reflect light. The phenomenon of lighting reflecting or bouncing off light from any surface is known as Reflection.
Extramarks NCERT Solutions for Class 8 Science Chapter 16 defines the law of reflection as:
The principle when a ray of light falls on a smooth surface and the angle of reflection is equivalent to the angle of incidence, also the incident ray, reflected ray, and normal to the surface, all lie in the same plane.
Laws of Reflection
- The incident ray is that ray of light that strikes a reflecting surface, while the reflected ray is the ray reflected.
- The normal is an imaginary line that is perpendicular to the reflecting surface.
- The incidence angle (I) is the angle formed by the incident ray and the normal. The angle between the reflected beam and the normal is called the angle of reflection (r).
- The angle of incidence (I) is always equal to the angle of reflection (r), (i=r) according to the laws of reflection. This is because the normal, the angle of incidence, and the angle of reflection are all on the same plane.
Types of Reflection
Extramarks NCERT Solutions for Class 8 Science Chapter 16 explains the two types of Reflection here:
Regular Reflection
Flat mirrors produce this form of reflection with a smooth surface, thus resulting in a crisp picture that can be easily seen. However, plane mirror pictures are always virtual, which means they can’t be gathered on a screen.
We can observe the pictures of reflection either digitally or physically in the case of curved mirrors with smooth surfaces. Curved mirrors can create actual or virtual pictures, which can be gathered and viewed (cannot be collected on a screen but only seen).
Diffused Reflection
Unlike mirrors, most natural surfaces are rough on the scale of light wavelengths, and as a result, parallel incident light rays are reflected unevenly or diffusely in many distinct directions. As a result, diffuse reflection aids in object recognition and is responsible for the ability to perceive most lighted surfaces from any angle.
Image formation in a plain mirror
- A plane mirror’s image is always virtual and upright, and the object and image are always equidistant from the mirror.
- A lateral inversion occurs when an image is created in a planar mirror.
Difference between Real and Virtual Image
The actual convergence of light beams creates a real image. A virtual image is generated when the outgoing rays from a spot on an object constantly diverge in optics. The picture looks to be situated around the clear divergence point. A virtual image cannot be projected onto a screen because the rays never indeed converge.
Multiple Reflections
- Due to numerous reflections, two mirrors inclined to each other produce several images .
- Infinite pictures are generated when an item is held between two parallel plane mirrors.
Extramarks NCERT Solutions for Class 8 Science Chapter 16 discusses the concept of Real and Virtual images and multiple reflections in the above section. To find answers to various such questions, refer to Extramarks today.
Dispersion
Another important aspect that we come across in Extramarks NCERT Solutions for Class 8 Science Chapter 16 is the concept of Dispersion.
When white light passes through a glass prism, it separates into its spectrum of colors (in sequence violet, indigo, blue, green, yellow, orange, and red), a process known as Dispersion.
Dispersion in a prism is the easiest method to describe the process: A spectrum of seven colors is generated when white light passes through a prism, demonstrating that white light is a blend of seven distinct hues. Prism serves as a separating medium for the seven hues. Refraction occurs when light strikes the glass prism. Because the wavelengths of specific light components fluctuate while the frequency remains constant, the variation in velocity through the glass medium causes each member to diverge at a different angle. The color red, which has the longest wavelength, deviates the least and forms the top portion of the spectrum, whereas violet, which has the shortest wavelength, deviates the most and includes the lower half.
Human Eye
Let us take a glance at the fundamental concept of Human Eyes by Extramarks NCERT Solutions for Class 8 Science Chapter 16.
The eye is one of the most powerful and sophisticated sense organs we humans possess. It helps visualize things and light, color, and depth perception. Furthermore, these sense organs can be compared to cameras in the way that they assist humans in seeing objects when light from the outside enters the objects. So, learning about the anatomy and operation of the human eye is fascinating. It also assists us in comprehending how a camera operates.
How do different organs in the Human Eyes function?
- Light enters the eye through a thin membrane called the cornea, which produces a transparent protrusion in the front of the eye.
- Iris is a black muscular diaphragm that regulates pupil size.
- The pupil is the iris’s tiny aperture in the middle.
- The lens behind the pupil assists in adjusting the focal length necessary to concentrate clearly on things at varying distances.
- The retina is the screen on which pictures are created. It is a fragile membrane that contains a vast number of photosensitive rods and cones.
- Bright light makes cones sensitive, whereas low light makes rods sensitive.
Visual Defects
- Visual deficiencies are the inability to see close items or view far away objects.
- The eye lens becomes clouded as people age, resulting in vision loss.
The Braille System
The idea of the Braille system is a significant part of Extramarks NCERT Solutions for Class 8 Science Chapter 16.
It was created specifically for the blind by Louis Braille. It’s raised-dot lettering that may be recognized by touching it with the fingertips. All Braille letters are made up of six dot locations organized in a rectangle with two columns of three dots each. A dot can be raised in any position.
Braille codes are made up of alphabet dot patterns, symbols, and other punctuation. It is carried out in a consistent manner and is based on Louis Braille’s original assignments. Various Braille codes are also used to notate mathematics, computer applications, music, and chess systems. The base of this code is still the 64 potential Braille letters and the added notational components.
NCERT Solutions for Class 8 Science Chapter 16 Exercise and Solutions
Students can find NCERT Solutions for all chapters and other study tools, including past years’ question papers, revision notes, extra problems, and more, on the Extramarks website. Click on the below links to view NCERT Solutions for Class 8 Science Chapter 16:
Class 8 Science Chapter 16: Very Short Answer Type Questions
Class 8 Science Chapter 16: Short Answer Type Questions
Class 8 Science Chapter 16: Long Answer Type Questions
Students may access NCERT Solutions for Class 8 Science Chapter 16 and other chapters by clicking here. In addition, students can also explore NCERT Solutions for other classes below.
By getting access to NCERT Solutions for Class 8 Science Chapter 16- Light, students can easily understand all the chapter’s concepts which are included in the detailed answers to the NCERT questions of this chapter.
NCERT Solutions Class 8 Science Chapter-wise List
Key Features of NCERT Solutions for Class 8 Science Chapter 16
Extramarks customizes its NCERT Solutions in such a way that it meets all the requirements of the students. Moreover, these solutions are prepared to the point in an elaborate manner. As a result, the Solutions are highly beneficial to students and help them understand things more easily and rapidly. Let us give you some reasons why you should choose us:
- Based on the NCERT standards, Extramarks has compiled the most relevant material in this chapter.
- These solutions also help students with time management during their examinations.
- These solutions have been prepared in a simple yet detailed manner for the students to understand complex and intricate topics easily and quickly.