Which electron transition results in the emission of energy? a. 3p to 3s c. 2s to 2p

The electron transition that results in the emission of energy is  3p to 3s.

According to the Bohr model of the atom, energy is emitted when an electron in an atom moves from a higher to a lower energy level. The energy emitted is equal to the energy difference between the two energy levels.

The energy level 3p is higher than the energy level 3s. Therefore, when an electron moves from 3p to 3s, there is emission of energy.

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electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia