Light: Mirrors and Lenses

Light: Mirrors and Lenses

This chapter introduces the fascinating world of light, focusing on mirrors and lenses. It begins by provoking curiosity through questions about the nature of images formed by different types of mirrors, such as whether mirrors can produce enlarged or diminished images, and why certain warnings appear on vehicle side-view mirrors. The chapter also hints at the practical applications of curved mirrors and lenses in daily life. It sets the stage for exploring spherical mirrors, their types, image formation, and the laws governing reflection, followed by an introduction to lenses and their properties. The chapter aims to deepen understanding of how light interacts with curved surfaces, both reflective and transparent, and how these principles are applied in technology and nature.

• Mirrors can produce images that are enlarged, diminished, or of the same size depending on their shape.
• Side-view mirrors on vehicles often carry warnings because of the nature of images formed by convex mirrors.
• Curved lines on reading glasses relate to the optical properties of lenses.
• Spherical mirrors are curved mirrors shaped like parts of hollow glass spheres.
• Lenses are transparent materials with curved surfaces that refract light.
• The chapter links theoretical concepts with practical applications in daily life and technology.
• 📌 Spherical mirrors: Mirrors with reflecting surfaces curved like a part of a hollow sphere.
• 📌 Concave mirror: A spherical mirror with the reflecting surface curved inward.
• 📌 Convex mirror: A spherical mirror with the reflecting surface curved outward.

10.1 What Are Spherical Mirrors?

Spherical mirrors are mirrors whose reflecting surfaces are curved like a part of a hollow glass sphere. They are broadly classified into two types based on the direction of their curvature: concave and convex mirrors. A concave mirror has its reflecting surface curved inward, resembling the inner surface of a sphere. This inward curvature causes light rays to converge upon reflection. Conversely, a convex mirror has its reflecting surface curved outward, like the outer surface of a sphere, causing light rays to diverge after reflection. These mirrors can be observed in everyday objects such as the shiny metallic spoon. When looking at the inner side of a spoon (concave), the image appears inverted and can be enlarged, whereas the outer side (convex) produces an erect but smaller image. Spherical mirrors are not made by slicing a glass sphere but by grinding and polishing flat glass into curved surfaces and then coating them with reflective material. Concave mirrors have the reflective coating on the outer curved surface, while convex mirrors have it on the inner curved surface. Understanding these basic types of spherical mirrors is crucial for exploring how images are formed and how these mirrors are used in practical applications.

• Spherical mirrors have reflecting surfaces shaped like parts of hollow spheres.
• Concave mirrors curve inward and converge light rays.
• Convex mirrors curve outward and diverge light rays.
• A shiny metallic spoon acts as a spherical mirror with concave and convex sides.
• Concave mirrors have reflective coating on the outer curved surface.
• Convex mirrors have reflective coating on the inner curved surface.
• 📌 Concave mirror: A mirror with reflecting surface curved inward.
• 📌 Convex mirror: A mirror with reflecting surface curved outward.
• 📌 Reflecting surface: The surface of a mirror that reflects light.