Subject A - Basic Electricity Flashcards
What is the most important law applicable to the study of electricity?
Ohm’s Law (E = I x R)
What are the elements of Ohm’s Law?
Voltage (E), Current (I), and Resistance (R)
What are four sources of electrical energy?
Thermal, light, pressure, and chemical
What does an electrical circuit consist of?
- A source (Battery).
- Resistance or load (Light bulb)
- Conductors (Wires)
What represents capacitance in an AC circuit?
A capacitor (Same as a Condenser)
What is the function of a capacitor?
To store electricity
What is the unit of measure for a capacitance?
Farad
What is the standard unit of measure for frequency?
Hertz
What is the basic component that only allows current to flow in one direction?
A diode (acts like a check valve)
What is inductance?
When voltage is induced by a magnetic flux lines in a coil in an AC circuit. The induced voltage is opposite in direction to the applied voltage and opposes any change in the alternating current.
What is an example of an inductor in a magneto?
The coil
What is impedance?
The total opposition for AC to flow caused by the combined effect of resistance, inductive reactance, and capacitive reactance in an AC circuit (Total resistance)
What causes opposition to the flow of current in AC circuit?
Inductive, and capacitance reactance.
What is the unit of measure for impedance?
Ohms
What is the general purpose of a resistor?
To limit current.
how may the value of a small, fixed resistor be determined?
By the color bands on the resistor.
What are two things that happen when current flows through a conductor?
A magnetic field is generated, and the conductor heats up.
What is the common name for the lines of force that make up a field surrounding magnet?
Magnetic flux lines.