You are in a fire truck heading directly toward a tunnel in a mountainside at 17m/s. you hear the truck's 90hz siren as well as its reflection from the mountainside. what beat frequency do you hear?

Hey there!:

Take the speed of sound to be 343m/s.

Direct frequency perceived by observer:

(343 + 17) / 343) * 90Hz = 94.460Hz

Change in frequency = ( 4.460 - 90 ) = 4.460Hz.  

90 - (4.460 x 2) = 81.08 Hz. indirect frequency heard by observer.  

Therefore :

Beat frequency = (94.460 - 81.08) = 13.38Hz.  

Hope this helps!

scorpions are,

c.arachnids

  scorpions are animals in the order scorpiones, under the class arachnida, which makes them a distant cousin of spiders

happy to

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