Answer:
The source is at a distance of 4.56 m from the first point.
Solution:
As per the question:
Separation distance between the points, d = 11.0 m
Sound level at the first point, L = 66.40 dB
Sound level at the second point, L'= 55.74 dB
Now,
where
I = Intensity of sound
Now,
Similarly,
Now,
Solving the above quadratic eqn, we get:
R = 4.56 m
In short, those arms are made of "stars, dust and gas". They are visible as spiral arms because they have a higher density of those objects than the space between them.
The arms are an area where the density of stars (and planets and other objects) is unusually high and where the start are young - recently formed- and this also gives those starts their visibility as young starts are also very bright.
Answer:
Total displacement = 0
Explanation:
He lives his front porch and still returns to his front porch.
Now, displacement is a vector quantity and as such, it is the distance between the initial point of movement and the final point of movement.
In this case the initial point is the same as the final point and thus the displacement is zero.
