Aperson wears a hearing aid that uniformly increases the intensity level of all audible frequencies of sound by 30.0 db. the hearing aid picks up sound having a frequency of 100 hz and an intensity of 1.3e-10 w/m2. what is the intensity delivered to the eardrum?

The intensity delivered to the ear drum is I' = 653.131x10^-11 w/m^2

Explanation:

The standard intensity Io = 10^{-12} w/m^2

The intensity of corresponds to an intensity level of

This is increased by the hearing aid by a factor of 30 dB

It now becomes 30 + 11.13 = 41.13 dB

This corresponds to an intensity of I'

10 log(I'/Io) = 41.13 dB

log (I'/Io) = 4.11

I'/Io + 10^4.11

I' = 10^{-12} x 12882.49 w/m^2

The intensity delivered to the ear drum is

I' = 653.131x10^-11 w/m^2

his week a heat wave will be hitting, and most of the country will be experiencing temperatures above average for july. due to humidity, the temperature outside can feel even warmer than it actually is. this adjusted temperature, often referred to as the “feels like” temperature is called the heat index. the chart shows the heat index, which is calculated based on temperature and relative humidity. use this chart to answer the following questions.