ELV Single Path Circuits Flashcards
What does the typical electrical grid look like ?
What is the typical structure of an atom ?
What is the difference btw conventional current flow and electron current flow ?
Conventional current = from +ve to -ve
Electron current = from -ve to +ve
What is static electricity ?
Static electricity form as a result of an imbalance in electrical charges on the surface of a material.
Explain the fundamental process that makes lightning static electricity.
What is Quantity of electricity ?
what is this symbol ?
what is this symbol ?
what is this component ?
what is this component ?
what is the basic arrangement of a circuit ?
what happens to the total resistance in an open circuit?
Resistance becomes infinity.
what happens to the total resistance in an short circuit?
Total resistance is reduced.
What is electrical power ?
Electrical power can be defined as the rate at which electrical energy is converted into another form of energy (e.g. light, heat, mechanical).
List the 3 electrical power equation.
What is electrical energy ?
Energy can be defined as the capacity to expend power over a period of time.
what is work ?
Work can be defined as a measure of force applied over a distance.
In what electrical terms are electrical appliances rated ?
Voltage and output power
What does the power rating of a resistor indicate ?
The power rating of a resistor indicates the maximum amount of heat it can dissipate continuously without causing damage.
What does the power rating of electrical equipment indicate ?
The power ratings of electrical equipment indicate their maximum output power
Calculate the maximum voltage that can safely be applied to a 45 Ω resistor that has a power rating of 5 W.
If a voltage greater than 15 V is applied, the heating caused by the resulting current would damage the resistor.
The physiological effects of electric current on the human body depends on ?
The magnitude of the current.
The duration of exposure.
The path of the current through the body.
Whether the current is alternating (a.c.) or direct (d.c.).
Explain the different zones in the shock chart
List some examples of magnetic effect of current
Alternators and generators.
Electric motors.
Transformers.
Relays and contactors.
What is heating effect of current ?
Occurs as a result of the work done to overcome the resistance of the conductor.
Eg>
Heating elements.
Spot welding.
Arc welding.