Answer:
80 dB
Explanation:
Sound intensity is inversely proportional to the square of the distance traveled by the sound.
Thus;
r1^2 divide by r2^2 = L2divideL1
where r= distance (m)
L= sound intensity (decibal dB)
8squared divide by 4 squared = L2 divide 20 dB
L2 = 4 × 20
L2= 80 dB
This means that the sound is increased from 20 dB to 80 dB.
Answer:
The answer to the question above is explained below
Explanation:
The loudness or sound intensity of the roaring truck engine is inversely proportional to the square of the distance.
r1^2 / r2^2 = L2/L1
Where, r1 and r2 = old distance and new distance respectively,
L1 and L2 = old sound intensity and new sound intensity respectively.
From the parameters given above,
r1=8m
r2=4m
L2=?
L1= 20dB
8^2 / 4^2 = L2 / 20 dB
L2 = 80 dB
The answer is 80 dB. Increased from 20 dB.
Decibel (dB), is a relative unit of measurement used for expressing the ratio between two physical quantities, usually electric power, or for measuring Sound intensity. Decibels measure the ratio of a given intensity to the threshold of hearing intensity.
Sound intensity, also known as acoustic intensity, is a vector describing the intensity of a sound is proportional to its amplitude squared.
