A student is standing 8 m from a roaring truck engine that is measured at 20 db. The student moves 4 m closer to the engine. What is the measured sound intensity at the new distance?

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.

they both go up but then go back down. they both end lower than they started. lastly, they both are competitive/the second on.

explanation: