9th Science Part 1: Reflection of Light Important Questions

Image Formation in a Plane Mirror

• A virtual image is formed in a plane mirror when light rays from an object bounce off the mirror and enter the viewer's eye, creating the illusion of an image behind the mirror.
• The light rays do not actually converge at a point, but the viewer perceives them as doing so, resulting in a virtual image that appears to be as far behind the mirror as the object is in front of it.

Total Internal Reflection

• Total internal reflection occurs when a light ray travels from a denser medium to a less dense medium and hits the surface at an angle greater than the critical angle.
• The angle of deviation, which is the angle between the incident ray and the reflected ray, is related to total internal reflection as it determines whether the light ray will be totally reflected or not.
• When the angle of incidence is greater than the critical angle, the angle of deviation is 90°, resulting in total internal reflection.

Law of Reflection

• The law of reflection states that the angle of incidence is equal to the angle of reflection, measured from the normal to the mirror.
• This law applies to all types of mirrors, including plane mirrors, concave mirrors, and convex mirrors.

Regular and Diffuse Reflection

• Regular reflection occurs when light rays Hit a smooth surface and bounce back, maintaining their direction and forming a clear image.
• Diffuse reflection occurs when light rays hit a rough surface and scatter in different directions, forming no clear image.
• Examples of regular reflection include mirrors and still water, while examples of diffuse reflection include rough surfaces and foam.

Prepare for your unit test with these important questions on the reflection of light. Understand the formation of virtual images in a plane mirror, the relationship between angle of deviation and total internal reflection, the law of reflection, and the difference between regular and diffuse reflection.