🔍 Key Concepts

• How most vehicle and small vessel engines are started electrically (think about cars and small trucks) • The difference between AC (alternating current) and DC (direct current) for starter motors • Why starting motors need very high current (amperage) for a short time

💭 Think About

• Which type of electricity is normally stored in onboard batteries, AC or DC? • When an engine is cranking to start, does it need high voltage with low current, or low voltage with very high current? Which option best matches that? • Look at the options that mention AC power: in normal marine practice, is AC usually used directly for cranking an auxiliary diesel, or is something else more common?

✅ Before You Answer

• Identify which choice clearly involves battery power and which involve AC systems • Check which option would reasonably supply high current at low-to-moderate voltage for a short burst • Eliminate any answers that would require shore power or ship’s AC generators just to start the auxiliary diesel