Which of the Following Is Essential for the Laser Action

question 39

Multiple Choice

Which of the following is essential for the laser action to occur between two energy levels of an atom?

• A)the lower level is metastable
• B)there are more atoms in the upper level than in the lower level
• C)there are more atoms in the lower level than in the upper level
• D)the lower level is the ground state
• E)the lasing material is a gas

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Definitions:

Welland Canal

A ship canal in Canada, connecting Lake Ontario and Lake Erie, facilitating navigation and trade by bypassing Niagara Falls.

Ballast Water

Water carried in ships' ballast tanks to improve stability and balance, which, when discharged, can introduce invasive aquatic species to new environments.

Autonomy

The degree to which a job provides the employee with the freedom, independence, and discretion to schedule their work and determine how it is done.

Responsibility

The state or fact of having a duty to deal with something or of having control over someone.