Physics X -Chapter 11: The Human Eye and Colourful World
Practice Human Eye and Colourful World MCQs. Learn eye structure, vision defects, atmospheric refraction, and dispersion for Class 10 science.
Quick Revision : The Human Eye and the Colourful World
- Power of Accommodation: Eye's ability to adjust focal length to see near and distant objects clearly.
- Near Point (Least Distance of Distinct Vision): Minimum distance for clear vision (~25 cm for normal eye).
- Far Point: Farthest point of clear vision (infinity for normal eye).
- Myopia (Near-sightedness): Image forms in front of retina; corrected using concave lens.
- Hypermetropia (Far-sightedness): Image forms behind retina; corrected using convex lens.
- Presbyopia: Age-related weakening of ciliary muscles; corrected using bifocal lenses.
- Cataract: Clouding of eye lens; treated surgically.
- Dispersion: Splitting of white light into seven colors (VIBGYOR) by a prism.
- Spectrum: Band of colors obtained after dispersion.
- Rainbow: Natural spectrum caused by dispersion of sunlight by water droplets.
- Atmospheric Refraction: Bending of light due to varying air density; causes twinkling of stars, advanced sunrise, delayed sunset.
- Twinkling of Stars: Due to atmospheric refraction of starlight; planets do not twinkle (extended source).
- Scattering of Light: Redirection of light by particles; explains blue sky, red sunrise/sunset, Tyndall effect.
- Tyndall Effect: Scattering of light by colloidal particles making the beam visible.
- Why Sky is Blue: Fine atmospheric particles scatter blue light more than red.
- Why Sun is Red at Sunrise/Sunset: Blue light scattered away, leaving longer wavelength red light.
- Danger Signals are Red: Red light is scattered least, travels farther through fog/smoke.
- Angle of Deviation (Prism): Angle between incident ray and emergent ray.
- Angle of Prism: Angle between two refracting surfaces.
- Prism Formula (Minimum Deviation): n = sin[(A+δₘ)/2] / sin(A/2).
Basic Level Questions
Chapter Summary: The Human Eye and the Colourful World
The Human Eye and the Colourful World, connects the physics of light with the biology of vision and the phenomena we observe in nature every day. It explains how the eye functions like a camera, the common defects that affect vision, and how lenses correct them. Beyond the eye, the chapter explores how light interacts with prisms and the atmosphere to create stunning effects like rainbows, blue skies, and red sunsets.
This chapter is highly scoring and frequently appears in board exams and competitive tests like NTSE and Olympiads. It includes diagram-based questions (human eye, prism, lens corrections), numerical problems on lens power and focal length, and conceptual explanations of natural phenomena. Questions often test application—why the sky is blue, why stars twinkle, how to correct vision defects—making it essential for both theory and practical understanding.
Our platform transforms this visual and conceptual chapter into easy-to-grasp, exam-ready knowledge. We offer a graded set of MCQs—from basic definitions to advanced numerical and reasoning problems—that cover every concept in the NCERT chapter. By practicing here, you reinforce your understanding of lens formulas, ray diagrams, and natural phenomena explanations. This targeted preparation builds your confidence, improves problem-solving speed, and ensures you can tackle any board or competitive exam question with clarity and accuracy.