Physics · Current Electricity

The potential difference is the amount of work done in moving a unit positive charge without acceleration from one point to another along any closed path between the two points.So, we need constant potential difference for establishing a steady current.

This option is not correct. A minimum potential difference is not always required to establish a steady current. The potential difference required depends on factors such as the resistance of the circuit and the desired current. 

This option is correct. A constant potential difference is required to establish a steady current in a circuit. If the potential difference changes, the current might also change accordingly. 

This option is not correct. While a maximum potential difference can result in a higher current in a circuit, it is not a requirement for establishing a steady current. 

This option is not correct. A varying (changing) potential difference can lead to a changing current, which is not characteristic of a steady current.