Question

Electric wires are usually made of copper as they have high resistance.
A. True
B. False

Answer 1

Hint: Electric wires are made to allow an electric current to pass through, and hence be transmitted from one place to another. Higher resistance reduces the current being transmitted.

Formula used: In this solution we will be using the following formulae;
\[I = \dfrac{V}{R}\] where \[I\] is the current flowing through a conductor, \[V\] is the current across it, and \[R\] is the resistance contributed by the conductor.

Complete step by step answer:
A statement is made; that electric wires are usually made of copper as they have high resistance. We are to answer if the statement is true or false.
To answer, we first ask the question: what are electric wires made for? Generally, electric wires are made to conduct electric current from one place to another. Wires can be said to allow transmission of current from source to load.
Now, it is said that copper is used because they have resistance.
So, to verify this part of the statement we need to investigate how current is influenced by the presence of resistance.
From ohm's law, we know that
\[I = \dfrac{V}{R}\] where \[I\] is the current flowing through a conductor, \[V\] is the current across it, and \[R\] is the resistance contributed by the conductor.
Hence, the current is inversely proportional to resistance, which means higher resistance, lower current.
Hence, a high resistant cannot be used as electric wires, the correct option is B.

Note: An alternate pattern of reasoning is that the power dissipated by an electric wire is proportional to the resistance. Hence, a higher resistance of electric wires would mean more electric power wasted in transmitting the electricity. Certainly not what we want. Also, we must note that copper is indeed used as electrical wires because they actually have low resistance.