Which term describes devices that obey Ohm's Law?

Which term describes devices that obey Ohm's Law?

• A. Ohmic
• B. Non-Ohmic
• C. LDR
• D. Diode

Answer: (A)

Ohm's Law describes a constant-resistance situation: V = IR. When a component’s resistance stays the same as voltage and current change, the current is directly proportional to the voltage. Such devices have a constant resistance and a straight-line V–I relationship through the origin, which means they obey Ohm's Law. This behavior is captured by the term Ohmic. In contrast, devices like a light-dependent resistor or a diode don’t keep a constant resistance. The LDR changes its resistance with light level, and a diode conducts in a nonlinear way with a threshold, so their current–voltage relationship isn’t proportional. Hence they are non-Ohmic.

Ohm's Law describes a constant-resistance situation: V = IR. When a component’s resistance stays the same as voltage and current change, the current is directly proportional to the voltage. Such devices have a constant resistance and a straight-line V–I relationship through the origin, which means they obey Ohm's Law. This behavior is captured by the term Ohmic.

In contrast, devices like a light-dependent resistor or a diode don’t keep a constant resistance. The LDR changes its resistance with light level, and a diode conducts in a nonlinear way with a threshold, so their current–voltage relationship isn’t proportional. Hence they are non-Ohmic.