Four objects—plastic scale, iron nail, wooden stick and aluminium foil—were tested in a simple electric circuit. Only two allowed the bulb to glow. Identify the conductors and justify your answer.
The conductors are the iron nail and aluminium foil. These materials are metals, which contain free electrons that can move easily, allowing electric current to pass through them and complete the circuit, causing the bulb to glow. Plastic scale and wooden stick are insulators; they do not allow current to flow, so the bulb would not glow with them.
Explanation
The conductors are the iron nail and aluminium foil. These materials are metals, which contain free electrons that can move easily, allowing electric current to pass through them and complete the circuit, causing the bulb to glow. Plastic scale and wooden stick are insulators; they do not allow current to flow, so the bulb would not glow with them.