ASVAB Electronic Information

• Volts伏特 - Pressure 电压U /Electromotive Force：电场中两点电势的差值。

• Amperes 安培 – Number of electrons current- 电流 I

• -          1 coulomb per second.

• -          I= Q电荷量库伦/T通过导体的时间

• Ohm 欧姆 – 电阻单位Resistance – Opposite flow of electrons.

• I电流= U电压/R 电阻

• Amperes = Voltage / Resistance

• Amperes = Watt/ Volt

• 当1V 电压的两端，通过1A 时， 电路电阻1R

• Insulator 绝缘体（Rubber、Wood）      Conductor导体（Copper 铜、Water）

• Watt-功率- Power- 1 J/S1焦耳、秒

• Watt = Volt*Ohm             Power = U 电压*Resistance

• F 功 – Work – 焦耳 J

• Frequency – 电流转换的频率 – Hz 赫兹- 1 complete cycle per second
  Impedance 阻抗- F/ Current

DC – Direct Current电流从正极流向负极

AC – Alternating Current - 电流向不确定

Cell电池- 1 cell = 1.5 volt

Battery = 2 or more cells

Moter发动机 -  convert electrical energy to kinetic energy.电能转为机械能

        Resistor 电阻器

• Electromagnetic – induction感应器 usually has iron in its core.

• 8 diodes in a bridge rectifier.桥式整流器

• When current flows through a wire, the following influences are present voltage, ohms, amper.

• Milli-henry毫亨---电感单位Inductor

• Radar operate at frequencies as high as 100,000 MHZ.

• Radio waves travel at the speed of light.

• Changing AC to DC is rectification整流、矫正.

• Insulated fitting 绝缘体can be used to splice结合soldering the wires together.

• Serial cable连续的电缆, 9 wires do serial cables used on computer.

• 60 Watt / 120 Volts = 0.5 Ampere

• No.12 Wire is smaller in diameter compared to No.6 Wire.

• A fuse with a higher-than- required rating may not work properly.

• Natural wire is whitish or natural.

• Conventional Current: from + to –

• Electricity Flows: from – to +

• Amplifier扩音器：三角形

• Heater: converts electrical energy to heat

• Bell and Buzzer汽笛: convert electrical energy to sound

• Inductor感应器: 电能转化为磁能储存起来

• Capacitor 电容器：容纳电荷store electricity. Capacitor connect it parallel. Capacitor oppose any change in voltage.

• Diode 二极管：单一方向流动、反向时阻断。

• Transistor晶体管：可变电流开关，通过输入电压控制输出电流

• Antenna天线

• Relay继电器：具有隔离功能的自动开关元件

• Operate Incandescent light bulb 白炽灯at less than its rated voltage, the bulb will burn dimmer 暗and last longer.

• Circuit 巡回

• At same current, 6mm wire required less voltage than 3mm wire.

• DC Motor has Armature电枢, Field Poles极点 and Yoke架.

• Rotor bars 电磁棒is AC induction motors感应电动器

• Current passed through a muscle causes it contract.

• RMS- Root Mean Square

• In a closed electrical circuit, one terminal端点 is always positive and one is negative.

• Television broadcast standard used in USA is NTSC.

• A circuit breaker trips错误、倾斜, find the operating handle half way between on and off.

• 12 AWG has the smallest wire compared with 10 AWG and 4 AWG. Smaller the wire, larger the number.

• 1 Path of electrical flow can be found in a series circuit.

• Low potential: 600 watts or less.

• The ground wire is always green.

• Oscillator振荡器: circuit produce high frequency AC.

• Plug an appliance designed for AC into DC, appliance will produce excessive heat.

• Transformer: increase or decrease AC Voltage.