Write brief answers to the following questions:
1. In the below figure you find that the bulb glows when an metal pin is placed between two ends of wire. Complete the following sentences on the bases of this fact.
Electric circuit
1. allows electric current to pass through the circuit and makes the bulb glow.
2. In the above figure if the iron nail is replaced by a plastic, will the bulb glow or not? Justify your answer.
i. .
ii. It acts as an .