The sound level at a point 5.0 m away from a point source is 40 dB. What will be the level at a point 50 m away from the source?

Question

Philoid · Accepted Answer

Let, be the sound level at a point 5 m) away from the point source and be the sound level at a distance of 50 m away from the point source.

∴

Sound level is given by:

According to the question,

⇒ ------------ (i)

⇒ ---------- (ii)

From (i) and (ii), we get:

----------- (iii)

Also,

-------- (iv)

From (iii) and (iv), we get:

⇒ ( Bases are same)

⇒

Thus, the sound level of a point 50 m away from the point source is 20 dB.