Identifying ohmic vs. non-ohmic components from I-V graph

Steps:

• Examine graph for X: straight line through origin indicates constant resistance (I ∝ V).
• Examine graph for Z: curved line shows varying resistance (non-linear I-V).
• Compare to ohmic definition: ohmic conductors obey Ohm's law (V = IR, straight line).
• Conclude X is ohmic (e.g., resistor), Z is non-ohmic (e.g., diode or lamp).

Why B is correct:

• B states X is ohmic and Z is non-ohmic, matching the linear vs. curved graph per Ohm's law (V = IR).

Why the others are wrong:

• A: Incorrect, as Z's curve violates Ohm's law for ohmic conductors.
• C: Incorrect, assumes both non-ohmic, but X's straight line fits ohmic behavior.
• D: Incorrect, reverses the components, ignoring X's linear characteristic.

Final answer: B