UPSC NDA 2 2019 General Ability Solved Paper

Concept:Loudness of sound is primarily determined by the intensity of the sound wave, which is directly related to its amplitude.Explanation:Loudness is the characteristic that makes a sound seem strong or weak.It is not the same as pitch (which depends on frequency) or velocity.The intensity $I$ of a sound wave is proportional to the square of its amplitude $A$: $I \propto A^{2}$.Greater amplitude means the wave carries more energy, producing a louder sound.The human ear perceives this intensity as loudness, though the relationship is not linear.Thus, among the given options, loudness depends on the amplitude of the sound waves.Answer:Option B: amplitude of the sound waves.