Which one of the following statements is not correct ?
[amp_mcq option1=”Ultrasonic waves cannot get reflected, refracted or absorbed.” option2=”Ultrasonic waves are used to detect the presence of defects like cracks, porosity, etc. in the internal structure of common structure materials.” option3=”Ultrasonic waves can be used for making holes in very hard materials like diamond.” option4=”Ultrasonic waves cannot travel through vacuum.” correct=”option1″]
This question was previously asked in
UPSC NDA-2 – 2017