Answer:
<u>because of the doppler effect</u>
Explanation:
<em>Remember</em>, the doppler effect refers to the changes in sound (frequency of sound) observed by a person who is in a position relative to the wave source.
In this example, we notice as the train comes closer to the boy, the sound becomes louder also increasing the pitch slightly, the doppler effect sets in when the train passes the boy because the boy notices a decrease in the pitch of the moving train.
We learn from the change in the observed sound of the train that the frequency of the sound is determined by the distance of the observer from the wave source.
In other words, the closer the source of the sound to the observer; the faster it travels to the observer, however, the farther it is; the lesser it is; the greater the sound heard.
Answer:
<em>B) The disturbance of particles in an area.</em>
Explanation:
<em>A wave involves transmission of energy from one place to another by the actual disturbance of the particles of the medium.</em>
<em />
Answer:
<em>The magnitude of the force is 10 N</em>
Explanation:
<u>Coulomb's Law</u>
The electrostatic force between two charged objects is directly proportional to the product of their charges and inversely proportional to the square of the distance between the two objects.
Written as a formula:
Where:
q1, q2 = the objects' charge
d= The distance between the objects
We have two identical charges of q1=q2=1 c separated by d=30000 m, thus the magnitude of the force is:
F = 10 N
The magnitude of the force is 10 N
