Answer:
Power of the speakers = 1.57 
Explanation:
There are speakers setup in a park and we have to find the power it would require to have intensity of sound to be
at a distance of 5 meter.
In one dimension the intensity is constant as the wave travels. In two or three dimensions, however, the intensity decreases as you get further from the source.
Intensity is inversely proportional to the square of the distance from the point of sound production.
Here area = 2
area = 157 


Power = ![10^{-8} \times 157Power = 1.57 [tex]\times 10^{-6} W](https://tex.z-dn.net/?f=10%5E%7B-8%7D%20%5Ctimes%20157%3C%2Fp%3E%3Cp%3E%3Cstrong%3EPower%20%3D%201.57%20%5Btex%5D%5Ctimes%2010%5E%7B-6%7D%20W)
1. a=Δv/Δt=(v-vo)/t=(0-25)/5=-25/5=-5 m/s²
The "-" sign shows us that the car has a slow motion
2.a=Δv/Δt=(v-vo)/t=(10-0)/4=10/4=2,5 m/s²
3.they do not have acceleration because they go at constant speed
Answer:
B. get smaller
Explanation:
The parallax angle of a star measured with respect to the Earth is inversely proportional to the distance of the star from the Earth:

where
is the parallax angle, measured in arcsec
d is the distance between the star and the Earth, measured in parsec
Therefore, if the star Alpha Centauri is moved farther from Earth, then d increases, and therefore the parallax angle will get smaller.