Respuesta :
Answer:
Explanation:
We shall convert decibel into intensity of sound in Watt / m²
75 decibell = 7.5 bell
7.5 = log ( I / 10⁻¹² )
I / 10⁻¹² = 10⁷°⁵
I = 10⁻¹² x 10⁷°⁵
= 10⁻⁴°⁵ watt / m²
Let power of the loudspeaker be P
intensity of sound 5m away will be given by the formula
P / 4π d² where , d is distance of the point at which intensity is measured
Puting the given values
P /4π 5² = 10⁻⁴°⁵
P = 4π 5² x 10⁻⁴°⁵
= 99.3 x 10⁻⁴ W
Answer:
answer is D
Explanation:
Changing the amplitude of a sound wave changes its loudness or intensity. If you are playing a guitar, the vibrations of the strings force nearby air molecules to compress and expand.
