Question

If the threshold for hearing increases 1000 times, the hearing loss is
A. 40 decibels
B. 50 decibels
C. 60 decibels
D. None of the above

Answer 1

Hint: Frequency shows the speed of vibrations of medium particles and therefore, the number of waves passing per second. Pitch is the sensation of frequencies. The measure of the loudness or softness of a sound is decided by its amplitude. The amplitude of sound waves is usually hooked into the force with which an object is formed to vibrate.

Complete answer: Children that are present beyond the age of 5 and few animals, like dogs can hear up to 25 kHz (1 kHz=1000 Hz). When people get older, their ears are sensitive to higher frequencies. Frequencies below 50 Hz are called infrasonic sounds or infrasound. According to the standards, the decibel level is about 50 dB in silence zones during day times. But, somehow it varied from 56 dB to 77 dB at day times and 51 dB to 75 dB at night. The construction work and sound pollution are caused by vehicles that disturb the peaceful environment of residential areas. It causes many discomforts and problems associated with mental disorders to patients in hospitals. Not only in hospitals, but sound pollution causes distractions and annoyance in institutional areas too. Thus, as per law and standards, 55 dB may be a limit set for residential areas in day times and 45 dB at night times. In the given and standard condition, sound intensity is 1000 times the edge, then the ratio of the intensity to the edge density is 103. So, the intensity is going to be 30 decibels.
Therefore, the correct answer is option D.

Note: In physics, sound is a vibration that propagates as an acoustic wave, through a transmission medium such as a gas, liquid or solid. Only acoustic waves that have frequencies lie between 20 Hz and 20 kHz.