GATE (Graduate Aptitude Test in Engineering) Physics: Questions 17 - 21 of 659
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Question 17
Appeared in Year: 2014
Question
MCQ▾For a system of two bosons, each of which can occupy any of the two energy levels 0 and , the mean energy of the system at a temperature with is given by,
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Question 18
Appeared in Year: 2014
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Short Answer▾A hydrogen atom is in the state
Where in denote the principal, orbital and magnetic quantum numbers, respectively. If is the angular momentum operator, the average value of is________ .
Question 19
Appeared in Year: 2015
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Short Answer▾The lattice parameters of an orthorhombic crystal are related by . In units of , the inter-planar separation between the planes is ________ (up to three decimal places)
Question 20
Appeared in Year: 2015
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Short Answer▾The bad gap of an intrinsic semiconductor is and . At 300 K, the Fermi level with respected to the edge of the valence band (in eV) is at ________ (up to three decimal places)
Question 21
Appeared in Year: 2014
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Short Answer▾If the half – life of an elementary particle moving with speed in the laboratory frame is , then the proper half – life is ________ .