The correct answer is: B. Coherent and monochromatic.
A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation. The term “laser” originated as an acronym for “light amplification by stimulated emission of radiation”.
Laser light is characterized by its high degree of coherence, monochromaticity, and brightness. Coherence refers to the fact that the light waves in a laser beam are all in phase with each other. This means that the peaks and troughs of the waves line up perfectly, which results in a very narrow, intense beam of light. Monochromaticity refers to the fact that laser light is of a single wavelength. This means that the light is all of the same color, which results in a very pure beam of light. Brightness refers to the amount of energy that is contained in a laser beam. Lasers can be very bright, which makes them useful for a variety of applications, such as cutting, welding, and surgery.
The other options are incorrect because:
- Option A is incorrect because laser light is coherent.
- Option C is incorrect because laser light is monochromatic.
- Option D is incorrect because laser light is both coherent and monochromatic.