Question

a person when asked to speak up,increases her sound level from 30dB to 60dB.The amount of power per unit area increased by? a)3000 times b)30 times c)2 times d)1000 times

Answer 1

d) 1000 times

Step-by-step explanation:

As we know that difference of sound level is given as

`L_2 - L_1 = 10 Log (I_2)/(I_1)`

so here we need to find the ratio of two intensity

it is given as

`Log(I_2)/(I_1) = ((L_2- L_1))/(10)`

`Log(I_2)/(I_1) = (60 - 30)/(10)`

`Log(I_2)/(I_1) = 3`

now we have

`(I_2)/(I_1) = 10^3`

so it is

d) 1000 times