Question
Download Solution PDFConsider the following statements:
1. The caesium beam and the hydrogen maser are the primary or absolute standards.
2. The rubidium vapour standard is based on the hyperfine transition in rubidium-78 gas, between the states F = 2 and F = 1.
3. The secondary standard of e.m.f. is the unsaturated Weston cell.
Which of the above statements are correct?
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFThe caesium beam and the hydrogen maser are the primary or absolute standards.
Rubidium standard is a frequency standard in which a specified hyperfine transition of electrons in rubidium-87 atoms is used to control the output frequency.
The secondary standard of Emf is the unsaturated Weston cell.
The unsaturated cell is similar to a saturated cell except that it does not have the cadmium sulphate crystals.
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