Electricity N4 Definitions Flashcards
What is electric charge?
Electric charge is a property of particles, like electrons and protons, that causes them to experience a force in an electric field.
What is the charge of an electron?
The charge of an electron is negative.
What happens when like charges come near each other?
Like charges repel each other.
What happens when opposite charges come near each other?
Opposite charges attract each other.
What is electric current?
Electric current is the flow of electric charge through a conductor, typically measured in amperes (A).
What is the unit of current?
The unit of current is the ampere (A).
What instrument is used to measure current?
Current is measured using an ammeter.
What is the formula relating charge, current, and time?
Q=I×tQ = I \times tQ=I×t, where QQQ is charge in coulombs (C), III is current in amperes (A), and ttt is time in seconds (s).
What is voltage (or potential difference)?
Voltage is the energy transferred per unit charge as a charge moves between two points in an electric circuit. It is measured in volts (V).
What is the unit of voltage?
The unit of voltage is the volt (V).
What instrument is used to measure voltage?
Voltage is measured using a voltmeter.
What is the relationship between energy, charge, and voltage?
V=EQV = \frac{E}{Q}V=QE, where VVV is voltage in volts, EEE is energy in joules (J), and QQQ is charge in coulombs (C).
What is resistance?
Resistance is the opposition to the flow of electric current in a material, measured in ohms (Ω).
What is the unit of resistance?
The unit of resistance is the ohm (Ω).
What is Ohm’s Law?
Ohm’s Law states that V=I×RV = I \times RV=I×R, where VVV is voltage in volts, III is current in amperes, and RRR is resistance.
What factors affect the resistance of a wire?
Resistance is affected by the material, length, thickness, and temperature of the wire.
In a series circuit, how is the current distributed?
In a series circuit, the current is the same at all points in the circuit.
In a series circuit, how is voltage distributed?
In a series circuit, the total voltage is the sum of the voltages across each component.
In a parallel circuit, how is the current distributed?
In a parallel circuit, the current splits between branches and may be different in each branch.
In a parallel circuit, how is voltage distributed?
In a parallel circuit, the voltage across each branch is the same.
What is electrical power?
Electrical power is the rate at which electrical energy is transferred by a circuit, measured in watts (W).
What is the formula for electrical power?
P=V×IP = V \times IP=V×I, where PPP is power in watts, VVV is voltage in volts, and III is current in amperes.
What is the relationship between power, energy, and time?
E=P×tE = P \times tE=P×t, where EEE is energy in joules (J), PPP is power in watts (W), and ttt is time in seconds (s).
What is efficiency, and how is it calculated?
Efficiency is a measure of how much input energy is converted to useful output energy. Efficiency=UsefulEnergyOutputTotalEnergyInput×100%\text{Efficiency} = \frac{\text{Useful Energy Output}}{\text{Total Energy Input}} \times 100\%Efficiency=TotalEnergyInputUsefulEnergyOutput×100%.
