Answer:
b. slow-moving streams.
Explanation:
In Fluid Mechanics, the Reynolds numbers indicates the existence of turbulence in fluid streams. Low Reynolds numbers are related with laminar flow. The Reynolds formula is:

The Reynolds number is directly proportional to fluid speed. Hence, slow-moving streams are a sound example of laminar flow. The correct answer is B.
How do fission nuclear reactions differ from fusion nuclear reactions?
A. Fission reactions involve the conversion of matter into energy, but fusion reactions do not.
B. Fusion reactions involve the conversion of matter into energy, but fission reactions do not.
C. Fission reactions are used to generate electricity for consumers, but fusion reactions are not.
D. Fusion reactions are used to generate electricity for consumers, but fission reactions are not.
Answer:
C
Explanation:
Both fission and fusion are nuclear reactions that produce energy, but their applications differs.
Fission is the splitting of a large (heavy, unstable) nucleus into smaller ones, and fusion is the process where nuclei of small atoms are combine together to form the nuclei of larger atoms releasing vast amounts of energy.
The correct answer is c. Fission reactions are used to generate electricity for consumers, but fusion reactions are not.
The physics of fusion is the process that makes the sun shine, and that makes the hydrogen bomb explode.
Humans hear frequencies from 20 Hz<span> (low) up to </span>20,000 Hz (high)
Answer:
0.903 seconds
Explanation:
To find how many seconds the acorn fall, we can use the formula for distance travelled with constant acceleration:
D = Vo*t + a*t^2/2,
where D is the distance travelled, Vo is the inicial speed, t is the time and a is the acceleration.
In our problem:
Vo = 0,
a = g = 9.81 m/s2,
D = 4 meters.
So, we can solve the equation to find the time:
4 = 0*t +9.81*t^2/2
4.905*t^2 = 4
t^2 = 4/4.905 = 0.8155
t = 0.903 seconds
Answer:
The silicon used to make monocrystalline solar cells has a high level of purity. ... Because of the way light interacts with a monocrystalline silicon layer, monocrystalline solar panels appear black in color.