The emission of photons without being aided by any external agency is called

• spontaneous emission

• stimulated emission

• relaxation

• de-excitation

The fact that all the photons coming from stimulated emission have the same frequency and phase is called

• coherence

• monochromatic

• transverse

• longitudinal

The minimum number of energy levels required to get a working laser is

• 3

• 2

• 1

• 4

The unidirectional nature of the laser beam is ensured by which component of Laser?

Which emission process causes the emission of incoherent photons in a laser?

• spontaneous emission

• stimulated emission

• forced emission

• de-excitation emission

What is the primary mechanism by which a laser amplifies light?

• reflection

• stimulated emission

• spontaneous emission

• absorption

Which type of laser uses a gas as its gain medium?

• solid-state laser

• semiconductor laser

• gas laser

• fiber laser

The process of energy being added to a system to achieve population inversion is known as

• excitation

• radiation

• pumping

• ionization