Question

consider the following
:copper, tungsten, chromium, aluminium, iron
which if the following can be used as a
heating element?
bulb filament?
​

Answer 1

Answer:

(i) filament of an electric bulb:

When choosing a material for a particular application, many different properties of materials must all be considered together (such as: melting point (MP), boiling point (BP), thermal conductivity, electrical resistivity, cost, etc.).

Incandescent light bulbs use heat generated by the resistance of the filament to create light by something called black body radiation. To get white light you need the filament to reach 2700-3300K to give off white yellow light. The reason tungsten is used is because it has the highest melting temperature of any element at 3600K.

For a typical incandescent light bulb, the Tungsten filament operates at approximately 2500 Celsius.

Hence, the filaments are made of tungsten.