{"id":85465,"date":"2025-06-01T03:18:15","date_gmt":"2025-06-01T03:18:15","guid":{"rendered":"https:\/\/exam.pscnotes.com\/mcq\/?p=85465"},"modified":"2025-06-01T03:18:15","modified_gmt":"2025-06-01T03:18:15","slug":"which-one-of-the-following-correctly-describes-the-principle-of-the-wo","status":"publish","type":"post","link":"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-correctly-describes-the-principle-of-the-wo\/","title":{"rendered":"Which one of the following correctly describes the principle of the wo"},"content":{"rendered":"

Which one of the following correctly describes the principle of the working of an atomic clock?<\/p>\n

[amp_mcq option1=”Vibration of a small quartz crystal” option2=”Simple harmonic motion of atoms inside a crystal” option3=”Resonant frequency in cesium (or rubidium) atom” option4=”Excitation and de-excitation of hydrogen atoms” correct=”option3″]<\/p>\n

\n
\n
This question was previously asked in<\/div>\n
UPSC CDS-1 – 2024<\/div>\n<\/div>\n
Download PDF<\/a>Attempt Online<\/a><\/div>\n<\/div>\n
\nThe correct answer is C. An atomic clock works based on the precise and stable resonant frequency of atoms, typically Cesium or Rubidium.
\n<\/section>\n
\nThe principle of an atomic clock relies on the natural, constant frequency associated with transitions between different energy levels of atoms, which are independent of external conditions and thus provide a highly stable frequency standard.
\n<\/section>\n
\nModern atomic clocks define the second based on the radiation frequency corresponding to the transition between two specific hyperfine levels of the ground state of the Cesium-133 atom. Rubidium clocks are also used, offering portability at slightly lower accuracy than Cesium primary standards. Quartz crystal vibrations are used in quartz clocks, which are less accurate than atomic clocks.
\n<\/section>\n","protected":false},"excerpt":{"rendered":"

Which one of the following correctly describes the principle of the working of an atomic clock? [amp_mcq option1=”Vibration of a small quartz crystal” option2=”Simple harmonic motion of atoms inside a crystal” option3=”Resonant frequency in cesium (or rubidium) atom” option4=”Excitation and de-excitation of hydrogen atoms” correct=”option3″] This question was previously asked in UPSC CDS-1 – 2024 … <\/p>\n

Detailed SolutionWhich one of the following correctly describes the principle of the wo<\/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":[1087],"tags":[1103,1236,1128],"class_list":["post-85465","post","type-post","status-publish","format-standard","hentry","category-upsc-cds-1","tag-1103","tag-measuring-instruments-and-scales","tag-physics","no-featured-image-padding"],"yoast_head":"\nWhich one of the following correctly describes the principle of the wo<\/title>\n<meta name=\"description\" content=\"The correct answer is C. An atomic clock works based on the precise and stable resonant frequency of atoms, typically Cesium or Rubidium. The principle of an atomic clock relies on the natural, constant frequency associated with transitions between different energy levels of atoms, which are independent of external conditions and thus provide a highly stable frequency standard.\" \/>\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-correctly-describes-the-principle-of-the-wo\/\" \/>\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 correctly describes the principle of the wo\" \/>\n<meta property=\"og:description\" content=\"The correct answer is C. An atomic clock works based on the precise and stable resonant frequency of atoms, typically Cesium or Rubidium. The principle of an atomic clock relies on the natural, constant frequency associated with transitions between different energy levels of atoms, which are independent of external conditions and thus provide a highly stable frequency standard.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/exam.pscnotes.com\/mcq\/which-one-of-the-following-correctly-describes-the-principle-of-the-wo\/\" \/>\n<meta property=\"og:site_name\" content=\"MCQ and Quiz for Exams\" \/>\n<meta property=\"article:published_time\" content=\"2025-06-01T03:18:15+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 correctly describes the principle of the wo","description":"The correct answer is C. 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