Answer : The correct answer is option C.
Explanation:
Astronomers have observed that light from the distant object in the universe is shifted towards the frequency of red color which indicates that those object are receding or moving away from the planet earth.This phenomena was termed as Red shift .Same thing goes for galaxies which are very far away from the planet earth.
Where as if galaxies were moving towards the the planet earth their light would have shifted toward the frequency of blue color termed as blue shift.
Hence, the correct answer is option C.
Inevitable manufacturing imperfections in optical fiber leads to birefringence, which is one cause of pulse broadening in fiber-optic communications. Such imperfections can be geometrical (lack of circular symmetry), due to stress applied to the optical fiber and/or due to bending of the fiber.
Answer:
The correct answer is option A, that is, one valence electron in its third energy shell and option C, that is, 11 electrons and 11 protons.
Explanation:
The outermost electrons and the ones that take part in the process of bonding are termed as valence electrons. The atomic number of sodium is 11, thus, it possesses 11 protons and the atoms are neutral so it suggests that sodium has 11 electrons. By electronic configuration, it can be seen that in sodium, two electrons are present in the first shell, 8 in the second, and only one electron in the third shell, that is, 2.8.1. The electron present in the third shell is the valence electron.
Sorry I cant I just need some points
