Question

.................... is used to make a solenoid type coil in an electric bulb.

• A. Nichrome
• B. Copper
• C. Tungsten
• D. Aluminium

Hint:

Tungsten’s high melting point and resilience make it ideal not only for light bulbs but also for other high-temperature applications, such as in electrical contacts, heating elements, and aerospace technologies.

Answer 1

The Correct Option is C

The filament in electric bulbs is typically made of tungsten due to its remarkable properties. Tungsten has the highest melting point of all metals, approximately 3422$^{\circ}$C (6192$^{\circ}$F), which is essential for its use in light bulbs. When current flows through the filament, it heats up due to the resistance it offers to the electric current, and it begins to glow, producing light.
The high melting point of tungsten allows the filament to reach high temperatures without melting. This is crucial because light bulbs need to operate at high temperatures to produce visible light.
Tungsten also has excellent durability and resistance to thermal shock, meaning it can withstand rapid temperature changes, which is common when light bulbs are turned on and off.
Additionally, tungsten has a low vapor pressure at high temperatures, which ensures that the filament does not evaporate easily, allowing it to last longer.
For these reasons, tungsten is the material of choice for electric bulb filaments.