Which one of the following metals is most commonly used for making filament of incandescent electric bulbs?

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Q: 98 (NDA-II/2022)

Which one of the following metals is most commonly used for making filament of incandescent electric bulbs?

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,50,6,3,0,3,50

The correct answer is option 4 - Tungsten.

Option 1 - Aluminium is not commonly used as a filament material in incandescent electric bulbs because it has a lower melting point and would not be able to withstand the high temperatures required for the filament to glow.

Option 2 - Silver is a good conductor of electricity but is not commonly used as a filament material in incandescent electric bulbs due to its high cost. Tungsten, on the other hand, is widely used as a filament material because it has a high melting point and can withstand the high temperatures needed for the bulb to produce light.

Option 3 - Copper is also a good conductor of electricity, but it is not commonly used as a filament material in incandescent electric bulbs. Copper has a lower melting point than tungsten and would not be able to withstand the high temperatures required for the filament to glow.

Option 4 - Tungsten is the correct answer. Tungsten has a very high melting point and can withstand the high temperatures produced in an incandescent electric bulb. It also has a high resistance to heat and does not easily break or deteriorate over time, making it a suitable choice for use as a filament in light bulbs.