Author Question: A sound source emits 20.0 W of acoustical power spread equally in all directions. The threshold of ... (Read 115 times)

jwb375

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A sound source emits 20.0 W of acoustical power spread equally in all directions. The threshold of hearing is 1.0  10-12 W/m2. What is the sound intensity level 30.0 m from the source?
 
  A) 92.5 dB
  B) 81.5 dB
  C) 1.77  10-3 dB
  D) 1.77  10-3 W
  E) -27.5 dB

Question 2

When a change of magnetic field occurs in a closed loop of wire,
 
  A) a voltage is induced in the wire.
  B) current is made to flow in the loop of wire.
  C) electromagnetic induction occurs.
  D) all of the above
  E) none of the above



Meganchabluk

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Answer to Question 1

A

Answer to Question 2

Awesome job my friend



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