🔍 Key Concepts

• DC motor brush sparking causes such as overload, poor commutation, or field/armature issues • Effect of changing generator voltage or speed on a DC propulsion motor • What happens to motor current and load when you change the motor field current

💭 Think About

• Think about which single adjustment you can make immediately and locally that most directly affects brush sparking on a DC motor • Consider how each option would change motor current, commutation quality, and load on the brushes • Ask yourself which action might actually make sparking worse rather than better, even if it sounds helpful at first

✅ Before You Answer

• For each choice, predict whether armature current will increase or decrease, and how that affects sparking • Check which action affects the motor itself versus affecting the generator or ship operations more generally • Verify which adjustment would most likely improve commutation at the brushes rather than simply reducing total power output