Answer:
f=896Hz
Explanation:
Given data
Vs(speed of the ambulance)={(104 km/h)*(1000m*(1 h/3600)}=28.9m/s
f(frequency of the ambulance siren)=821 Hz
v(speed of sound)=345 m/s
Vo(speed of the observer)=0 m/s
To find
f(The ambulance is approaching the person)
Solution
From Doppler effect

As the ambulance approaches the we assign a positive sign for speed "vs" of the ambulance
So

Substitute the values from given data

It would be accelerating at -9.8 m/s^2 so it’s velocity would be equal to -9.8•1.1 so the answer is 10.78m/s
Answer:
Kepler's Third Law
T = 2 π r 3 G M E . T = 2 π r 3 G M E . For an ellipse, recall that the semi-major axis is one-half the sum of the perihelion and the aphelion. For a circular orbit, the semi-major axis (a) is the same as the radius for the orbit.