To develop this problem we will apply the concepts related to the Doppler effect. The frequency of sound perceive by observer changes from source emitting the sound. The frequency received by observer 
is more than the frequency emitted by the source. The expression to find the frequency received by the person is,
= Frequency of the source
= Speed of sound
= Speed of source
The velocity of the ambulance is
Replacing at the expression to frequency of observer we have,
Therefore the frequency receive by observer is 878Hz
Answer: Im not entirly sure but I think It's D all the above. I think all but B because I never really heard of that but if you look in our history I think that happen im not sure I would wait untill you know that somone knows for sure.
Explanation:
Answer: 6s
Explanation:
Vs=32m/s speed at beginning of slowing down
Vf=0m/s stop speed
a= -6 m/s² acceleration
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Use equation for acceleration :
a=(Vf-Vs)/t
a*t=Vf-Vs
t=(Vf-Vs)/a
t=(0-36)/-6
t=-36/-6
t=6 s
Answer:
No, the sound produced by screeching brakes is not a useful form of energy, because it does not contribute to stopping the car.
