Question

what does the symbol “∝” mean? how is it used between current, voltage, and resistance?

Explanation:

The symbol "∝" means "is proportional to". In the context of current (I), voltage (V), and resistance (R), according to Ohm's law $V = IR$. When resistance is constant, current is proportional to voltage, written as $I\propto V$. When voltage is constant, current is inversely - proportional to resistance, written as $I\propto\frac{1}{R}$.

Answer:

The symbol "∝" means "is proportional to". In the context of current, voltage and resistance, $I\propto V$ (when $R$ is constant) and $I\propto\frac{1}{R}$ (when $V$ is constant).