Which of the following is a common cause of faulty resistors?

A common cause of faulty resistors is overheating. Resistors are designed to limit current flow and dissipate energy as heat. When they are operated beyond their specified power ratings or in conditions where they cannot effectively transfer heat away, they can overheat. This excessive heat can cause physical damage, including changes in resistance values, or complete failure.

While incorrect installation can lead to issues in circuit performance, it is not a direct cause of a resistor becoming faulty in the way that overheating is. Overheating typically leads to a decrease in reliability and lifespan of the component, which is a crucial aspect to consider in any electronic circuit design and maintenance.

Accumulation of dirt can lead to circuit problems, but it is more associated with connections and contact issues rather than the resistors themselves becoming faulty. Excessive resistance usually refers to a resistor that is operating properly within its specifications; it’s not a cause of fault in itself. Hence, overheating stands out as a more direct cause of resistor failure.