A molecule of DNA (deoxyribonucleic acid) lies along a straight line. It is 2.778 µm long. The ends of the molecule become singly ionized; negative on one end, positive on the other. The helical molecule acts as a spring and compresses 1% upon becoming charged. Determine the effective spring constant of the molecule. Take into account the compressed length when calculating the distance between the ends of the molecule. The Coulomb constant is 8.99 × 109 N · m2 /C 2 . Answer in units of N/m.

the answer is to check all of them! they all apply well at least i think so!

be subject to a force andchange its motion

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