Practice Population Inversion & Light Amplification (2) - Lasers

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6 sample questions

Question 1.
What is population inversion?
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Think about the balance of energy states in atoms.
Question 2.
Why is pumping necessary for a laser?
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Consider how energy influences the states of atoms.
3Question 3.
What condition is necessary for population inversion?
- N1>N2
- N2=N1
- N2>N1
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Think about what 'inversion' means.
4Question 4.
True or false: Stimulated emission is less significant than spontaneous emission.
- True
- False
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What dominates when population inversion is achieved?
Question 5.
Given a system where there are 150 atoms in the ground state, how many need to be in the excited state for population inversion?
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Think about how N2 must be greater than N1.
Question 6.
A laser operates with a pumped medium resulting in a 4x increase in photon production due to stimulated emission. If initially there were 500 photons, how many are there after stimulation?
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Consider how stimulated emission leads to a multiplying effect on the number of photons.

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