If you are describing a circuit breaker then its electromagnetic trip component will operate in the event of a line*-to-ground (*not 'phase'!) short circuit. The thermal overload component will only operate in the event of a sustained overload.

When determining how reliable something is, a benchmark called "Mean Time Between Failures" is often used. It's usually represented as "MTBF". That means, the average time that a component will operate continuously.

It refers to an interior part that something cannot operate without.

The wheel or pulley that is not turning is locked up and will have to be replaced. If it is a component such as the air conditioner compressor, or water pump, alternator , etc. then that component will have to be replaced. do not operate the engine while this component is locked up or you will destroy the engine

The computer seizes to operate as no data processing will be made. The CPU is the principal component of a digital computer(the heart).