When you step on a roach, the roach applies an equal and opposite force on your foot
as your foot applies to the roach (we don't advocate killing insects this way, especially if
you are barefoot),
True or false?

True.

Explanation:

Newton's Third Law states that for every action, there is an equal and opposite reaction. This means that the roach is applying the exact same force that you are applying to it by stepping on it.

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