超星 - L8-句子词汇 - 查题吧

单选题

Power Supplies are electronic circuits designed to convert AC ( Alternating Current ) to DC ( Direct Current ) at any desired level.

A. 交流电
B. 转换
C. 直流电
D. 电源供应器

单选题

A power supply can be broken down into a series of blocks: transformer, rectifier, filter, and voltage regulator, each of which performs a particular function.

A. 被分成一系列
B. 模块
C. 执行
D. 特定功能

单选题

The transformer can convert AC electricity from one voltage to another with little loss of power. Most power supplies use a step-down transformer to reduce the high AC mains voltage ( 230V or 110V ) to a safer low AC voltage .

A. 电源
B. 变压器
C. 损耗
D. 降压

单选题

The rectifier uses the ability of a diode to conduct during one half cycle of AC to convert AC to DC. A single diode rectifier only uses the positive half part of the AC wave to produce a half-wave varying DC.

A. 整流器
B. 正半周期
C. 二极管
D. 导通

单选题

A bridge rectifier uses four diodes connected in a bridge network to produce a full-wave varying DC output .

A. 桥式网络
B. 四个二极管
C. 桥式整流器
D. 直流输出

单选题

Filtering is performed by a large value electrolytic capacitor connected across the DC supply, supplying current to the output when the varying DC voltage from the rectifier is falling.

A. 滤波
B. 电解电容器
C. 变化直流电压
D. 整流器

单选题

The diagram Fig. 3-9 shows the unsmoothed varying DC (dotted line) before filtering and the smoothed DC (solid line) after filtering .

A. 未平滑的
B. 虚线
C. 滤波后
D. 平滑直流实线

单选题

The capacitor charges quickly near the peak of the varying DC, and then discharges as it supplies current to the output, smooths the DC from varying greatly to a small ripple.

A. 放电
B. 电容器
C. 快速充电
D. 小波纹

单选题

Voltage regulators are circuits designed to maintain the DC output at constant amplitude. Voltage regulator ICs are available with fixed（typically 5, 12 and 15V）or variable output voltages.

A. 可变输出电压
B. 恒定幅度
C. 稳压器
D. 保持

单选题

The regulated DC output is very smooth with no ripple. It is suitable for all electronic circuits.

A. 稳压的直流输出
B. 非常平稳
C. 电子电路
D. 适用于

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