{"id":87584,"date":"2025-06-01T06:48:12","date_gmt":"2025-06-01T06:48:12","guid":{"rendered":"https:\/\/exam.pscnotes.com\/mcq\/?p=87584"},"modified":"2025-06-01T06:48:12","modified_gmt":"2025-06-01T06:48:12","slug":"which-one-of-the-following-statements-about-the-refractive-index-of-a","status":"publish","type":"post","link":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-about-the-refractive-index-of-a\/","title":{"rendered":"Which one of the following statements about the refractive index of a"},"content":{"rendered":"

Which one of the following statements about the refractive index of a material medium with respect to air is correct ?<\/p>\n

[amp_mcq option1=”It can be either positive or negative” option2=”It can have zero value” option3=”It is unity for all materials” option4=”It is always greater than one” correct=”option4″]<\/p>\n

\n
\n
This question was previously asked in<\/div>\n
UPSC NDA-1 – 2018<\/div>\n<\/div>\n
Download PDF<\/a>Attempt Online<\/a><\/div>\n<\/div>\n
\nThe refractive index of a material medium ($n_m$) with respect to air ($n_{air}$) is defined as the ratio of the speed of light in air ($v_{air}$) to the speed of light in the medium ($v_m$). Since the speed of light in any material medium is always less than the speed of light in vacuum (and approximately less than the speed of light in air), the ratio $v_{air} \/ v_m$ will always be greater than 1 for any material medium (except vacuum or air itself, where the refractive index is 1).
\n<\/section>\n
\nRefractive index is a measure of how much the speed of light is reduced in a medium compared to air\/vacuum. A higher refractive index indicates a slower speed of light in the medium and greater bending of light.
\n<\/section>\n
\nRefractive index values are typically positive. A refractive index of zero or negative would imply unusual optical properties, not characteristic of common materials. The refractive index of air with respect to vacuum is slightly greater than 1, but often approximated as 1. The refractive index of a medium with respect to vacuum is always greater than or equal to 1.
\n<\/section>\n","protected":false},"excerpt":{"rendered":"

Which one of the following statements about the refractive index of a material medium with respect to air is correct ? [amp_mcq option1=”It can be either positive or negative” option2=”It can have zero value” option3=”It is unity for all materials” option4=”It is always greater than one” correct=”option4″] This question was previously asked in UPSC NDA-1 … <\/p>\n

Detailed SolutionWhich one of the following statements about the refractive index of a<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1093],"tags":[1114,1153,1128],"class_list":["post-87584","post","type-post","status-publish","format-standard","hentry","category-upsc-nda-1","tag-1114","tag-optics","tag-physics","no-featured-image-padding"],"yoast_head":"\nWhich one of the following statements about the refractive index of a<\/title>\n<meta name=\"description\" content=\"The refractive index of a material medium ($n_m$) with respect to air ($n_{air}$) is defined as the ratio of the speed of light in air ($v_{air}$) to the speed of light in the medium ($v_m$). Since the speed of light in any material medium is always less than the speed of light in vacuum (and approximately less than the speed of light in air), the ratio $v_{air} \/ v_m$ will always be greater than 1 for any material medium (except vacuum or air itself, where the refractive index is 1). Refractive index is a measure of how much the speed of light is reduced in a medium compared to air\/vacuum. A higher refractive index indicates a slower speed of light in the medium and greater bending of light.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-about-the-refractive-index-of-a\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"Which one of the following statements about the refractive index of a\" \/>\n<meta property=\"og:description\" content=\"The refractive index of a material medium ($n_m$) with respect to air ($n_{air}$) is defined as the ratio of the speed of light in air ($v_{air}$) to the speed of light in the medium ($v_m$). Since the speed of light in any material medium is always less than the speed of light in vacuum (and approximately less than the speed of light in air), the ratio $v_{air} \/ v_m$ will always be greater than 1 for any material medium (except vacuum or air itself, where the refractive index is 1). Refractive index is a measure of how much the speed of light is reduced in a medium compared to air\/vacuum. A higher refractive index indicates a slower speed of light in the medium and greater bending of light.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-about-the-refractive-index-of-a\/\" \/>\n<meta property=\"og:site_name\" content=\"MCQ and Quiz for Exams\" \/>\n<meta property=\"article:published_time\" content=\"2025-06-01T06:48:12+00:00\" \/>\n<meta name=\"author\" content=\"rawan239\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Written by\" \/>\n\t<meta name=\"twitter:data1\" content=\"rawan239\" \/>\n\t<meta name=\"twitter:label2\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data2\" content=\"1 minute\" \/>\n<!-- \/ Yoast SEO Premium plugin. -->","yoast_head_json":{"title":"Which one of the following statements about the refractive index of a","description":"The refractive index of a material medium ($n_m$) with respect to air ($n_{air}$) is defined as the ratio of the speed of light in air ($v_{air}$) to the speed of light in the medium ($v_m$). 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A higher refractive index indicates a slower speed of light in the medium and greater bending of light.","og_url":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-about-the-refractive-index-of-a\/","og_site_name":"MCQ and Quiz for Exams","article_published_time":"2025-06-01T06:48:12+00:00","author":"rawan239","twitter_card":"summary_large_image","twitter_misc":{"Written by":"rawan239","Est. reading time":"1 minute"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-about-the-refractive-index-of-a\/","url":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-statements-about-the-refractive-index-of-a\/","name":"Which one of the following statements about the refractive index of a","isPartOf":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#website"},"datePublished":"2025-06-01T06:48:12+00:00","dateModified":"2025-06-01T06:48:12+00:00","author":{"@id":"https:\/\/exam.pscnotes.com\/mcq\/#\/schema\/person\/5807dafeb27d2ec82344d6cbd6c3d209"},"description":"The refractive index of a material medium ($n_m$) with respect to air ($n_{air}$) is defined as the ratio of the speed of light in air ($v_{air}$) to the speed of light in the medium ($v_m$). 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