A lighter block (3 kg) and a heavier block (12 kg) sit on a frictionless surface. Both blocks are initially at rest. The same force of 6 N then pushes to the right on each block for a distance of 9 m. What are the initial kinetic energies of the blocks? K_1i = K_2i = What are the changes in kinetic energy of the blocks? Delta K_1i = Delta K_2i = What are the final kinetic energies of the blocks? K_1f = K_2f = What are the initial momenta of the blocks? p_1i = p_2i = What are the final momenta of the blocks? p_1f = p_2f = What are the changes in momenta of the blocks?

see earlier

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