Physics
2021 · Paper 1
Take it one question at a time. Try an answer, then check your understanding.
Complete GATE PH 2021 Paper 1 overview, original pages and practice · Timed previous-paper practice
Questions 25–27 of 65. Imported answers require review unless explicitly marked reviewed.
Question 15
Open questionPHMSQ1 markNeeds review
To sustain lasing action in a three-level laser as shown in the figure, necessary condition(s) is(are)
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Open questionPHMSQ1 markNeeds review
If
is a solution of the differential equation
where
is an integer and the prime (
) denotes differentiation with respect to
, then acceptable plot(s) of
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Open questionPHNAT1 markNeeds review
The donor concentration in a sample of n-type silicon is increased by a factor of 100. Assuming the sample to be non-degenerate, the shift in the Fermi level (in meV) at 300 K (rounded off to the nearest integer) is _____.
(Given:
meV at 300 K)Log in to check the answer
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