Answer:
A Ray I believe since it sounds like it.
-Velocity is the speed of any moving object in a given direction, whilst Speed is the rate of an object's ability to move.
-Velocity can change if the direction or time is changed, the basic equation of velocity is: v = d/t
v - velocity
d - distance
t - time
If one of these factors change, it affects the other.
Hope this answers the question!
Answer:
A )
Explanation:
This change in frequency observation occur due to doppler effect
if the wave source moves,In the time between one wave peak being emitted and the next, the source will have moved so that the shells will no longer be concentric. The wavefronts will get closer together in front of the source as it travels and will be further apart behind it. (see the graph)
when the person standing still in front of the ambulance, he will observe a <em>higher frequency </em>than before as the source travels towards them.

The pitch we hear depends on the frequency of the sound wave.
A high frequency corresponds to a high pitch
as we hear a higher frequency , it makes the <em>pitch higher</em> too
Answer:
45.1/3× 3.1/2 + 50.1/2× 2.1/2
=136/3. 7/2.+ 101/2× 5/2
=952/6 + 505/2
=( 952+ 1515)/6
=411.16
Explanation:
Make sure to read and go with it
Answer:
47 mW
Explanation:
The average value of the Poynting vector, S = 0.939 W/m² = Intensity of wave, I
S = I S
Also, I = P/A where P = Et, P = power of electromagnetic wave, E = energy of electromagnetic wave in time t and t = time = 1 min = 60 s and A = area = lb since the electromagnetic waves falls on area equal to that of a rectangle.
So, S = Et/A
E = SA/t
= Slb/t
= 0.939 W/m² × 1.5 m × 2.0 m/60 s
= 2.817 W/60 s
= 0.047 W
= 47 mW
So, 47 mW of electromagnetic energy falls on the area in 1.0 minute.