The answer is A. an object that allows some light to pass through
Explanation:
hope this would be the right answer ..
Answer:
a: increasing the positive charge of the positively charged object and increasing the negative charge of the negatively charged object
Explanation:
Answer: 
Explanation:
Given
At an elevation of 
, spacecraft is dropping vertically at a speed of 
Final velocity of the spacecraft is 
using equation of motion i.e. 
Insert the values
Therefore, magnitude of acceleration is .
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.
