Final answer:
Most powerboats use a 12-volt DC electrical system for starting and powering instruments, pumps, and navigation lights. They are recharged by an alternator driven by the boat's engine.
Step-by-step explanation:
Most powerboats use a 12-volt Direct Current (DC) electrical system for starting and powering their instruments, pumps, and navigation lights. This system is based on batteries that provide the necessary voltage and current to run the boat's electrical components.
The batteries are recharged by an alternator, which is driven by the boat's engine and converts mechanical energy into electrical energy. The alternator supplies power to the battery, keeping it charged while the engine is running. When the boat's engine is not running, the batteries can still provide power for a limited time. However, if the batteries are depleted, the boat's electrical system will not function until the batteries are recharged.
In addition to the 12-volt DC system, powerboats may also have a 120-volt Alternating Current (AC) system. This system allows the boat to power larger appliances, such as a refrigerator or air conditioning unit when connected to shore power or a generator.