Commercial Driver’s License (CDL) Practice Exam

The air compressor is connected to the engine through gears or a v-belt because this configuration allows the compressor to be driven directly by the engine’s power. This mechanical connection ensures that the compressor operates efficiently and maintains the necessary pressure for the air braking system while the engine is running.

Using gears allows for a direct power transfer, which is reliable for consistent air compressor performance, while a v-belt can provide some flexibility in alignment and tension adjustments. This setup is crucial in commercial vehicles where air brakes are commonly used, as the compressor must maintain adequate air pressure to ensure safe braking performance.

Alternatively, hydraulic lines, electrical wiring, and pneumatic tubes are not suitable for driving the air compressor because they either serve different purposes in vehicle systems or are not designed to handle the mechanical demands required to power an air compressor effectively. These other methods do not provide the direct and dependable link necessary for the air compressor's operation.