Alight bulb connects to a battery. a second, identical light bulb connects in parallel to the first light bulb. the connecting wires have negligible resistance. when the switch is closed, the original light bulb will:
o no longer light.
o become brighter.
o become dimmer.
o experience no change in brightness.

d

Explanation:

Suppose V is the voltage of battery and R is the resistance of bulb

so Power drop for initial stage

When another identical bulb of same resistance is applied in parallel so voltage Drop across both the resistor will be same i.e. V

so Power consumed  

so there is no change in power and hence no dip in brightness  

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