Question

Connecting wires in an electric circuit are made of …….
A. copper
B. silicon
C. tin
D. lead

Answer 1

Hint: The connecting wires in the circuit must not consume any power or energy. Therefore, the metal from which the connecting wires are made must have a very low resistivity. Hence, among the given options select the metal that has the least resistivity.

Complete step by step answer:
Suppose we want to light a bulb. The bulb as a resistance R. For the bulb to glow, a current must flow through the bulb. Therefore, we have to connect a cell across the bulb, which will create a potential difference across the bulb.
For a specific brightness of the bulb, we must connect a cell of specific emf. Let that required emf of the cell be V.
The terminals of the cell are connected to the bulb with the help of wire. Now note that these wires must just act as connectors and must not be involved in the circuit. In other words, the connecting wires must not act as components that will consume some energy. If the wires consume some energy, the bulb will not glow at the required brightness.
Therefore, the metal from which the wires are made must have very low resistivity. Copper has a very low resistivity among the metals. Hence, copper is used to make the connecting wires.
In addition, copper has high ductility, which makes it easier to make wires from copper.
Hence, the correct answer is option A.

Note:
The order of resistivity of the given option is as follows:
Copper < tin < lead < silicon
Hence, among the given options, silicon has the highest resistivity.