<span>Because they occur at an atomic level, changing the actual structure of the thing.
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Answer:
B) collision is inelastic because they stick together after collision and share a common final velocity Vf
C) M1V1 + M2V2 = (M1 + M2)Vf
D) Vf = 6.33m/s
E) force = 3040N
Explanation:
Detailed explanation and calculation is shown in the image below
To solve this problem we will start from the given concept in which the number of turns is equivalent to the length of the thread per circumference of spool. That is:

Where,
l = length of the thread
= circumference of spool
For \phi we have that,

For l we have that
l = 62.8m
Finally the number of Turns would be,



Therefore the number of turns of thread on the spool are 1000turns.
Answer:
2. The hydrogen atom has quantized energy levels.
Explanation:
The Bohr model of the atom states that the structure of the atom is quantized, that is, that electrons can only orbit the nucleus in specific orbits with a fixed radius. Therefore, the electron cannot be in energy levels that do not correspond to these quantized levels.
No they do not there not humans