The sound level at 1.0 m from a certain talking person talking is 60 db. you are surrounded by five such people, all 1.0 m from you and all talking equally loud at the same time. the threshold of hearing is 1.0 × 10-12 w/m2. what sound level are you being exposed to? you can neglect any absorption, reflection, or interference of the sound. the threshold of hearing is 1.0 × 10-12 w/m2.

66.98 db

Explanation:

We know that

L_T= Total signal level in db

n= number of sources

L_S= signal level from signal source.

= 66.98 db

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards