Answer:
A) As the ambulance's siren moves toward a stationary hearer, the quality of sound will have a higher pitch
B) As the ambulance's siren moves away from a stationary hearer, the quality of sound will have a lower pitch.
Explanation:
From Doppler effect, the closer the source of sound gets to the observer, the higher the frequency and in turn the higher the pitch.
Meanwhile, the farther a source goes from an observer, the lower the frequency of the sound and also the lower the pitch.
Thus, as the ambulance's siren moves toward a stationary hearer, the quality of sound will have a higher pitch.
As the ambulance's siren moves away from a stationary hearer, the quality of sound will have a lower pitch.
Answer:
The two moments must be the same:
p1=p2
m1v1=m2v2
v2=(m1v1)/m2
v2=(90 kg x 0.9 m/s)/110kg=0.7 m/s
Answer:
There are three kinds of rock: igneous, sedimentary, and metamorphic.
Trees can be a renewable source , we use them to breath , we make paper out of them , we make houses and etc.
i hope this helps