Answer:
a) The car was moving at a speed of 
b) The negative sign of
denotes that the observer is coming towards the police car which is the source of the sound.
c) 
Explanation:
Given:
- original frequency of the source,

- speed of the source,

- velocity of the obstacle car be,

- speed of sound,

- observed frequency,

<u>Using the equation from the Doppler's effect:</u>



a)
The car was moving at a speed of 
b)
The negative sign of
denotes that the observer is coming towards the police car which is the source of the sound.
c)
Now when, 
Then, 
Using the Doppler's eq.:


Two light waves will interfere constructively if the path-length difference between them is a whole number.
<h3>
SUPERPOSITION</h3>
The principle of superposition state that, when two or more waves meet at a point, the resultant displacement at that point is equal to the sum of the displacements of the individual waves at that point.
Interference of waves can either be constructive, or destructive.
The two light waves, initially emitted in phase, will interfere constructively with maximum amplitude if the path-length difference between them is a whole number of wavelenght 1λ, 2λ, 3λ, 4λ etc
The equivalent phase differences between the waves will be 2
or 360 degrees, 4
or 720 degrees, 6
1080 degrees etc
Therefore, the two light waves, initially emitted in phase, will interfere constructively with maximum amplitude if the path-length difference between them is a whole number.
Learn more about Interference here: brainly.com/question/25310724
5.5 s
Explanation:
The time it takes for the ball to reach its maximum height can be calculated using

since
at the top of its trajectory. Plugging in the numbers,

Answer:
Explanation:
A. Using
Sinစ= y/ L = 0.013/2.7= 0.00481
စ=0.28°
B.here we use
Alpha= πsinစa/lambda
= π x (0.0351)sin(0.28)/588E-9m
= 9.1*10^-2rad
C.we use
I(စ)/Im= (sin alpha/alpha) ²
So
{= (sin0.091/0.091)²
= 3*10^-4