🔍 Key Concepts

• Dynamotor construction – how a single rotating machine can perform both DC motor and DC generator functions • Relationship between field windings, armatures, and power sources (like batteries) • Typical applications of dynamotors in older radio and communication systems

💭 Think About

• Think about what makes a dynamotor different from having a separate motor and generator – how are they combined mechanically and electrically? • Consider how a dynamotor is usually powered in practical installations (for example, on older vessels or in radio gear). • Ask yourself whether combining functions into one machine would normally increase, decrease, or leave efficiency about the same compared with two separate machines.

✅ Before You Answer

• Verify whether a dynamotor shares a common field winding between its motor and generator sections. • Confirm if dynamotors in classic marine/aviation use are normally driven by DC battery power or by some other source. • Think critically about whether a dynamotor is inherently of higher efficiency than a separate motor-generator set before choosing an option that claims multiple statements are true.