Sound is more effectively transmitted into a stethoscope by direct contact rather than through the air, and it is further intensified by being concentrated on the smaller area of the eardrum. It is reasonable to assume that sound is transmitted into a stethoscope 100 times as effectively compared with transmission though the air. What, then, is the gain in decibels produced by a stethoscope that has a sound gathering area of 15.0 cm2 , and concentrates the sound onto two eardrums with a total area of 0.900 cm2 with an efficiency of 40.0% ?

(a) Ear trumpets were never very common, but they did aid people with hearing losses by gathering sound over a large area and concentrating it on the smaller area of the eardrum. What decibel increase does an ear trumpet produce if its sound gathering area is 900 cm2 and the area of the eardrum is 0.500 cm2 , but the trumpet only has an efficiency of 5.00% in transmitting the sound to the eardrum? (b) Comment on the usefulness of the decibel increase found in part (a).

The scream of a little screaming monster reaches the near-side of a sound-insulating wall with an intensity of 95 dB.   The manufacturer of the wall claims the material in the wall will reduce the sound energy by 99%. If this is true, what intensity, in decibels, of sound will be heard on the other side of the wall?

The intensity of sound high as a multiple of the average minimum threshold of hearing intensity is related to the decibel level D or loudness of sound according to I=10^D/10 (A) express 10^D/10 using radical notation  10^D/10= (B)The background noise level of a relatively quiet room has a decibel reading of 31. Find the intensity of this noise level round your answer to decimal places (C)a decibel reading of 132 is at the threshold of pain. if I2 is the intensity of the threshold and I1 is the intensity found and part B express or a show I2/I1 as a power of 10 I2/I1=10^ approximate the ratio(round your answer to two decimal places) _____x10^10