Question

A wire with resistance r is connected to the terminals of a 30 v battery. part a what is the potential difference δvends between the ends of the wire?

Answer 1

30 V

Step-by-step explanation:

When the wire is connected to the terminal of the battery, the potential difference across the wire becomes equal to the emf produced by the battery. This can be seen by using also Kirchhoff second law, which states that the sum of the p.d. across the components of a closed loop in a circuit must be equal to the sum of the emf of the batteries in the circuit:

`\sum emf = \sum V_i`

In this case, we have

`\sum emf = 30 V` (there is only one battery)

Therefore,

`\sum V_i = 30 V`

and since there is only one resistor, it means that the p.d. across the resistor is 30 V.