What is a laser? Environmental Engineering Mcqs February 28, 2019 BILAL KHATTAK0 A.Electro-magnetic waves B.Ultrasonic waves C.Supersonic waves D.Light amplification by stimulated emission of radiationRelated Mcqs:Laser is an acronym for light amplification byThe atmospheric greenhouse effect is produced mainly by the __________?A fathometer works on the principle ofLED stands for?Laser is a device to produceA geodimeter is based on the principle ofA photochemical reaction isHow many stimuli from a different source fall on our eye:The wavelength of which of the following is the largest?Which of the following has a wavelength shorter than that of violet light?