Relationship between Current, Voltage and Resistance

Current, voltage and resistance are interconnected as stated by Ohm’s law.
Ohm’s law is applied to circuits with a constant temperature and is described by the equation V=IR. The voltage (V) across a component equals the current (I) through that component times its resistance (R).
Voltage (V) is the energy transferred per unit of charge passed and is measured in Volts (V).
Current (I) is the flow of electric charge and is measured in Amperes or Amps (A).
Resistance (R) is a measure of the opposition to the passage of current and is measured in Ohms (Ω).
In a parallel circuit, the total resistance decreases as more components are added. However, in a series circuit, the total resistance increases as more components are added.
Components in a circuit contribute their own resistance, which is dependent upon factors such as the length of the conductor, the cross-sectional area, and the nature of the material.
For resistors in series, the total resistance (R_total) is the sum of the individual resistances: R1 + R2 + R3…
For resistors in parallel, 1/R_total = 1/R1 + 1/R2 + 1/R3…
A higher resistance results in a lower current for a given voltage, according to Ohm’s Law. Conversely, a lower resistance results in a higher current.
A greater potential difference (voltage) results in a greater current for a given resistance, also as per Ohm’s Law.
For a fixed voltage, the higher the resistance of the component, the lower the current that flows through it.
The current in a series circuit is the same everywhere, yet the voltage splits.
On the other hand, in a parallel circuit, while the current splits, the voltage remains the same across all components.
If the voltage is doubled, the current is also doubled given the resistance stays the same.
Likewise, if the resistance is doubled, the current is halved assuming the voltage stays the same.
The relationship between current, voltage and resistance is linear for most conductors, meaning that if you graph current versus voltage, you’ll get a straight line.
Non-Ohmic conductors, like diodes or thermistors, do not exhibit this linearity, and their current-voltage graph is not a straight line.