Static and Friction
What is the smallest part of a substance that retains the properties of that substance.
The atom
List one of the main parts of a circuit
Source of electric energy, electric load, control device, connectors
What is the name of a device used to measure potential difference (voltage) that is connected in parallel with load or the energy source?
Voltmeter
What device is used to measure resistance that is connected in parallel in a circuit and uses ¨ohm Ω¨ as its unit
Ohmeter
How well an electrical device converts electrical energy into useful energy is the definition of what?
Efficiency
Does an object that gains electrons become positively or negatively charged
Negatively charged
Differentiate the flow of electrons between static electricity and current electricity
In static electricity the flow of electrons is unpredictable while in current it is steady
What is the purpose of an ammeter?
To measure electric current
What happens when current flows in the circuit with no load, resistance becomes very low, and current flow is high
Short circuit
What is the rate at which electrical energy is produced or used in a given time (hint: measured in watts)
Electrical power
What do insulators do
Inhibit or prevent the movement of electrons
What is a circuit?
Electric charges (electrons) that flow through a conductor in a controlled way
What do fuses and circuit breakers protect and prevent?
Fuses and circuit breakers protect against overload of the circuit and prevent fire
What does a variable resistor allow?
A variable resistor allows you to change the resistance in a circuit
What converts the chemical energy of a fuel directly into electrical energy by electrochemical reactions?
Fuel Cell
What does the law of electric charges say
Objects with the same (like) charges repel, objects with opposite (unlike) charges attract, charged objects will sometimes attract neutral objects
How can you identify a series circuit
The flow of electrons follows only one path and it is achieved by connecting loads in a chain, one after another
When more loads are added to a series circuit what happens to the current? What about a parallel circuit?
When more loads are added to a series circuit, current decreases. When more loads are added to a parallel circuit, overall current increases.
What are the four factors that affect resistance
Type of material, cross-sectional area, length, temperature
How is your electricity bill calculated
cost to operate = power used x time x cost of electricity
Define electric discharge
Electric Discharge is the rapid transfer of electric charge from one object to another (shock) (removing + or – charge to become neutral)
How can you identify a parallel circuit?
Electrons can flow more than one way and loads are on at least 2 different branches of wires connected to the electrical source.
What is the symbol and unit used to measure current
Symbol is ¨I," the unit is ¨(A) / Amperes¨
What is the filament in an incandescent light bulb
The filament in an incandescent light bulb is a thinner wire and different material than the conducting wire providing the electric current
What do electric cells do?
Converts chemical energy into electrical energy