ISA Utility Arborist Practice Test 2026 – 400 Free Practice Questions to Pass the Exam

The correct answer is based on the fundamental principles of Ohm's law, which states that the current (I) flowing through a conductor between two points is directly proportional to the voltage (V) across the two points and inversely proportional to the resistance (R) of the conductor. This relationship is mathematically represented as I = V/R.

When the voltage increases while the resistance remains constant, the equation can be interpreted as follows: since resistance (R) does not change, an increase in voltage (V) will lead to a corresponding increase in current (I). This is because with higher voltage available, more electrical energy per unit charge is pushed through the circuit, resulting in a higher flow of current.

In practical terms, if you imagine an electrical circuit as a flow of water through a pipe, increasing the pressure (voltage) in the pipe while keeping the size of the pipe (resistance) constant will lead to an increased flow of water (current). Thus, the direct relationship between voltage and current under constant resistance clarifies why the current increases when voltage is increased.