Question

A device for producing a highly intense and coherent (wave in the same phase) beam of light is called?
(A) LASER
(B) MASER
(C) searchlight
(D) none of these

Answer 1

Hint: -
Here we need to name the device which produces a highly intense beam of light. It Is given that the light is coherent, by coherent we mean a beam of photons like particles of light waves that have the same frequency. The waveforms are all identical.

Complete step by step solution:
We are given some options such as LASER, maser and searchlight.
Searchlight uses a light source which must be bright enough and the mirror is used to increase the intensity. The light beam that comes out is not coherent. Next is LASER, it stands for light amplification by stimulated emission of radiation. The light is generated by optical amplification which is achieved by stimulated emission of electromagnetic radiation. The property of light beams coming out of LASER is that it is coherent and highly intense and focused. So the correct answer is LASER and the correct option is (A)

Additional Information:
There are also naturally discovered MASERS which can be found in interstellar space

Note:
MASER stands for microwave amplification by stimulated emission of radiation. The light produced by MASER is also coherent but it does not fall in the visible spectrum. The light is the microwave that we cannot see. MASER emits a photon of lower frequency and longer wavelength compared to LASER. Both have wide applications.