Answer: The frequency heard will be f = 275.675Hz
Explanation: When an object emitting sound is moving, it occurs a phenomenon called Doppler shift or Doppler effect. What happens is that the sound gets higher when the moving object comes closer the observer and becomes lower after it passes, This change is due to the quantity of waves that passes through an area in an unit of time.
The formula to calculate the Doppler effect is as follows
f = (
) · f₀
f is the observed frequency;
c is the speed of sound;
Vs is velocity of the source;
f₀ is the emitted frequency of source;
Substituting and calculating,
f =
· 300
f = 275.675 Hz
Thus, the frequency heard by the police officer is 275.675Hz.
The resultant displacement of the man is 109.77 km in the direction N60°E.
<h3>Displacement</h3>
Displacement is the distance travelled in a specified direction.
To calculate displacement, the straight line from starting point to end point of travel is taken and calculated.
<h3>Resultant displacement of the man </h3>
In the example above, a man walks 95 km, East, then 55 km, north.
The two distances form a right-angled triangle with two sides 95 and 55 units. The hypotenuse gives the resultant displacement, D.
Using Pythagoras rule:
D^2 = 95^2 + 55^2
D^2 = 12050
D = 109.77
Thus, the resultant displacement is 109.77 km
To calculate the direction:
Let the direction be y
y + x = 90°
tan x = 55/95
tanx x = 0.578
x = 30°
Then, y = 90 - 30
y = 60°
Therefore, the resultant displacement of the man is 109.77 km in the direction N60°E.
Learn more about displacement at: brainly.com/question/321442

<u>Given :</u>








<u>Let's Slove :</u><u> </u>



<span>The diameter of the Moon is 3,474 km. Now, let's compare this to the Earth. The diameter of the Earth is 12,742 km. This means that the Moon is approximately 27% the size of the Earth.</span>
Answer:
AM has longer wavelength
Explanation:
The relation between the wavelength and teh frequency is given by
v = f x λ
Where, f is the frequency and λ be the wavelength.
It shows that the wavelength is inversely proportional to the frequency.
So, higher the frequency, smaller be the wavelength.
So, FM has high frequency than AM, thus, FM has lower wavelength as compared to AM.