Question

An electric filament bulb can be worked from
A. DC supply only
B. AC supply only
C. Battery supply only
D. All above

Answer 1

Hint: Recall the basics about an electric bulb. Also, recall the basics about an electric filament in an electric bulb. Check the process by which an electric bulb glows. Hence, check what is the basic requirement for the glowing of an electric filament in an electric bulb and which type of electric current is required for the glowing of an electric bulb.

Complete answer:
The main work of an electric filament bulb is to glow when an electric current is passed through the electric filament. The only requirement for glowing of the electric filament in the electric bulb is the electric current. The electric current required to glow the bulb can be supplied from a direct current supply (DC supply), alternating current supply (AC supply) or battery supply.Therefore, the electric current can be worked from DC supply, AC supply and battery supply.

Hence, the correct option is D.

Additional information:
The general type of the electric bulb is incandescent bulb.In an incandescent bulb, the filament in the bulb is heated with an electric current. This filament in the bulb is heated to such a temperature that it glows and produces light.The filament used in the incandescent bulb is made up of tungsten as it can withstand high temperature.

Note:The students may think that in an alternating current supply or AC supply, there are not full cycles of electric current. So, it should not be used for glowing the electric filament in an electric bulb. But the ultimate requirement for the flowing of filament in an electric bulb is the electric current of any type. Hence the alternating current supply or AC supply can also be used for glowing electric filament in an electric bulb.