Among the media listed in the image the one with minimum speed of light is important to identify. Option A is wrong. Water has speed 2.25 × 10⁸ m/s which is the highest speed among the listed material media. Water has a relatively low refractive index of 1.33. Option B is wrong. Turpentine oil has speed 2.04 × 10⁸ m/s. Its refractive index is approximately 1.47. This is slower than water but not the minimum in the list. Option C is CORRECT. The image states: प्रकाश की गति किस माध्यम से जाते हुए न्यूनतम होती है — काँच माध्यम में (क्योंकि काँच का अपवर्तनांक ज्यादा होता है). Among the commonly cited transparent media in the image glass has the minimum speed at 2 × 10⁸ m/s with refractive index 1.5. Rock salt also has 1.96 × 10⁸ m/s (similar to glass) but the image specifically mentions glass as having minimum speed among the transparent media. Higher refractive index means greater slowing of light. Option D is wrong. Vacuum has the MAXIMUM speed of light at 3 × 10⁸ m/s and refractive index of exactly 1 by definition. Vacuum is not a material medium and light travels fastest in it.
FAQ
Common questions and clear answers for this topic.
Optics is the branch of physics that studies the behavior of light, including its reflection, refraction, and interaction with lenses and mirrors.
Reflection is the bouncing back of light when it strikes a surface, while refraction is the bending of light as it passes from one medium to another with a different optical density.
A lens is a transparent optical device with curved surfaces that refracts light to converge or diverge rays, commonly classified as convex (converging) or concave (diverging).
The speed of light in a vacuum is approximately 3 x 10^8 meters per second, denoted by the symbol c.
Total internal reflection occurs when light traveling from a denser medium to a rarer medium strikes the boundary at an angle greater than the critical angle, causing it to be completely reflected back into the denser medium.
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