A transistor designated as BC 147 signifies that it is constructed from____________?
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Answer: B. silicon
Explanation
Semiconductor manufacturing coding standards use specific letters like B to designate silicon as the base material. The letter C in the prefix indicates that the semiconductor device is designed to function as a low-frequency transistor. Therefore, the alphanumeric designation BC 147 explicitly identifies a silicon-based electronic transistor component. Pro-Electron standardization assigns standardized prefixes to European semiconductor components for easy identification. Early semiconductor technology utilized germanium extensively before silicon became the dominant material for transistors. Silicon offers superior thermal stability and higher breakdown voltage characteristics compared to older semiconductor materials.
Electronics technicians and engineers read component part numbers to determine material composition and operating parameters. Circuit repair manuals specify exact replacement transistors using standard industry naming conventions. Educational electronics laboratories frequently utilize BC147 silicon transistors for basic amplifier experiments. Germanium was used in early transistors, but the BC prefix specifically denotes silicon rather than germanium. Carbon is utilized in resistors rather than serving as the primary semiconductor material for transistor fabrication. None of the above is incorrect because silicon correctly identifies the semiconductor material of the BC 147.
- Subject
- Engineering
- Category
- Electrical Engineering
- Topic
- —
- Difficulty
- medium
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