Suppose a photon with an energy of 1.60 ev strikes a piece of metal. if the electron that it hits loses 0.800 ev leaving the metal, what is the kinetic energy of the electron once it has broken free of the metal surface?

To solve this problem it is necessary to apply the concepts related to the change of Energy in photons and the conservation of energy.

From the theory we could consider that the energy change is subject to

Where

Initial Energy

Energy loses

Replacing we have that

Therefore the Kinetic energy of the electron once it has broken free of the metal surface is 0.8eV

0.55x745.7j and a calculator

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