The power rating printed on an electric motor's nameplate denotes____________?
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Answer: D. the output power available at the shaft
Explanation
The nameplate on an electric motor specifies the guaranteed mechanical output power at the shaft. Power ratings account for internal electrical and mechanical losses occurring within the motor body. Designating shaft output power helps users select correct mechanical drives for specific machines. Electric motors convert electrical energy into mechanical work delivered through a rotating shaft. Nameplate specifications provide essential operational data for safe installation and usage. Power output is commonly measured in kilowatts or horsepower units on industrial nameplates.
Factory technicians read motor nameplates to ensure equipment matches mechanical load requirements. Incorrect power selection can lead to motor burnout or inefficient industrial production processes. Standardized ratings ensure compatibility between electrical supply systems and driven machinery. Power drawn in kilowatts represents electrical input power rather than mechanical output power. Power drawn in kilovolt-amperes measures apparent electrical power supplied to alternating current systems. Gross power ignores internal motor losses and does not reflect usable shaft output.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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