Aproton circulates in a cyclotron, beginning approximately at rest at the center. whenever it passes through the gap between dees, the electric potential difference between the dees is 220 v. (a) by how much does its kinetic energy increase with each passage through the gap? (b) what is its kinetic energy as it completes 127 passes through the gap? (c) let r127 be the radius of the proton's circular path as it completes those 127 passes and enters a dee, and let r128be its next radius, as it enters a dee the next time. by what percentage does the radius increase when it changes from r127 to r128? that is, what is percentage increase = (r128 - r127)/r127*100%?

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