Why are optoisolators often used in conjunction with solid-state circuits that control 120 VAC circuits?
The correct answer is C: Optoisolators provide an electrical isolation between a control circuit and the circuit being switched. Why are optoisolators often used in conjunction with solid-state circuits that control 120 VAC circuits is that optoisolators provide an electrical isolation between a control circuit and the circuit being switched. Optoisolators provide safety isolation. For amateur radio operators, this is important for safety. Understanding this helps when designing control circuits.
Exam Tip
Optoisolators with 120VAC control = provide electrical isolation between control and switched circuit. Think 'O'ptoisolator = 'I'solation. Optoisolators provide safety isolation. Not low-impedance link, not impedance matching, not reflected light - just electrical isolation.
Memory Aid
"Optoisolators with 120VAC control = provide electrical isolation between control and switched circuit. Think 'O'ptoisolator = 'I'solation. Optoisolators provide safety isolation. Important for safety."
Real-World Application
Optoisolators with solid-state circuits controlling 120 VAC: They're used because optoisolators provide an electrical isolation between a control circuit and the circuit being switched. This protects the control circuit from high voltage. This is the reason - electrical isolation.
Key Concepts
Why Other Options Are Wrong
Option A: Incorrect. Optoisolators providing low-impedance link isn't the reason - optoisolators provide isolation. Low-impedance link isn't the reason.
Option B: Incorrect. Optoisolators providing impedance matching isn't the reason - optoisolators provide isolation. Impedance matching isn't the reason.
Option D: Incorrect. Optoisolators eliminating reflected light effects isn't the reason - optoisolators provide isolation. Reflected light isn't the reason.
题目解析
The correct answer is C: Optoisolators provide an electrical isolation between a control circuit and the circuit being switched. Why are optoisolators often used in conjunction with solid-state circuits that control 120 VAC circuits is that optoisolators provide an electrical isolation between a control circuit and the circuit being switched. Optoisolators provide safety isolation. For amateur radio operators, this is important for safety. Understanding this helps when designing control circuits.
考试技巧
Optoisolators with 120VAC control = provide electrical isolation between control and switched circuit. Think 'O'ptoisolator = 'I'solation. Optoisolators provide safety isolation. Not low-impedance link, not impedance matching, not reflected light - just electrical isolation.
记忆口诀
Optoisolators with 120VAC control = provide electrical isolation between control and switched circuit. Think 'O'ptoisolator = 'I'solation. Optoisolators provide safety isolation. Important for safety.
实际应用示例
Optoisolators with solid-state circuits controlling 120 VAC: They're used because optoisolators provide an electrical isolation between a control circuit and the circuit being switched. This protects the control circuit from high voltage. This is the reason - electrical isolation.
错误选项分析
Option A: Incorrect. Optoisolators providing low-impedance link isn't the reason - optoisolators provide isolation. Low-impedance link isn't the reason. Option B: Incorrect. Optoisolators providing impedance matching isn't the reason - optoisolators provide isolation. Impedance matching isn't the reason. Option D: Incorrect. Optoisolators eliminating reflected light effects isn't the reason - optoisolators provide isolation. Reflected light isn't the reason.
知识点
Optoisolators, Used in conjunction with, Solid-state circuits, Control 120 VAC circuits, Electrical isolation
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.