Explanation:
It is given that,
The signal to a speaker causes 0.5 amps of current, [tex]I_1=0.5\ A[/tex]
The signal level is increased to 2.5 amps, [tex]I_2=2.5\ A[/tex]
We need to find the gain to the nearest decibel. The decibel gain formula of the speaker is given by :
[tex]db=20\ log(\dfrac{I_2}{I_1})[/tex]
[tex]db=20\ log(\dfrac{2.5}{0.5})[/tex]
db = 13.97 db
or
db = 14 db
So, the gain pf the speaker is 14 db. Hence, this is the required solution.