Question

The filament of the bulb is of?
A. Mercury
B. Copper
C. Tungsten
D. None of these

Answer 1

Hint: Copper wire has very low resistance. Tungsten has a higher amount of electrical resistance. That is why tungsten even has less electrical conductivity than copper.

Complete step-by-step solution:
To solve this question, first, we have to know about the incandescent bulb. An incandescent light bulb is an electrical light with a wire called filament, which is warmed until it glows. The filament is covered in a tube to protect from oxidation. By means of terminals or wires in the container, current is provided to the filament. The bulb socket allows for mechanical assistance and electrical contact.
Now, let us find the solution from the given options -
Both UV and CFL bulbs contain very small amounts of mercury, less than 1/100th of the
quantity contained in the mercury thermometer. Much like all CFL bulbs there is no risk to
human health if the bulb glass is intact and not damaged.
Copper wire cannot be used to create an electrical bulb filament, because copper wire has very low resistance. Therefore, the light does not shine until the current is removed. It will also melt-the filament must be white-hot for any application.
Tungsten is used as a filament in incandescent light bulbs as it has the highest melting point of any metal and the higher the temperature, the greater the output and the whiter the light.
Thus, the right answer is option C. i.e., Tungsten.

Note: Mercury, an integral part of the CFL, enables the bulb to be an effective light source.
Mercury-vapor lamp is a gas-discharge lamp which is used to vaporize electrical arcs.