Conservation Laws
Conservations just means stays the same.
An open system can allow things to stay or leave.
A system is a group of two or more things that are separate from their environment.
If there is no boundary there is an open system.
Closed systems obey conservation laws such as momentum, total energy, and charge.
Electric Charge
Net charge is the sum of all charges in a system.
Charges can be transferred and movement through a conductor is called current.
If the charge keeps going around it is a circuit.
There are two types of charges, positive and negative charges.
Moving charge creates work in the system.
Positive and Negative Charge
Electric charges can be positive or negative.
Neutral objects have the same amount of positive and negative charges.
Unlike charges attract each other and like charges repel each other.
If you hold a charged object to a neutral one it becomes polarized.
No attraction between neutrally charge objects.
An object becomes polarized, when a charged and neutral object meet, the opposite charges on the neutral object attract and like ones move away creation an attraction.
Elementary Charge
Elementary charge is the smallest unit of charge an object can have.
Charge is quantized, the smallest it can be is 1.6*10^-19.
Electrons have negative elementary charge and protons have positive elementary charge.
Charge quantizations means no charges in the middle.
Electrostatic Induction
Electrostatic induction is the ability for charges in one object to affect charges in another object.
Charged objects can be charged through friction or a conductor/insulator.
Induction is next to conduction is touching.
Electrons move, not protons.
Insulators have fixed electrons, conductors have free electrons.
Calculating Electric Force
Two charges next to each other is just Electric Force.
Conservations just means stays the same.
An open system can allow things to stay or leave.
A system is a group of two or more things that are separate from their environment.
If there is no boundary there is an open system.
Closed systems obey conservation laws such as momentum, total energy, and charge.
Electric Charge
Net charge is the sum of all charges in a system.
Charges can be transferred and movement through a conductor is called current.
If the charge keeps going around it is a circuit.
There are two types of charges, positive and negative charges.
Moving charge creates work in the system.
Positive and Negative Charge
Electric charges can be positive or negative.
Neutral objects have the same amount of positive and negative charges.
Unlike charges attract each other and like charges repel each other.
If you hold a charged object to a neutral one it becomes polarized.
No attraction between neutrally charge objects.
An object becomes polarized, when a charged and neutral object meet, the opposite charges on the neutral object attract and like ones move away creation an attraction.
Elementary Charge
Elementary charge is the smallest unit of charge an object can have.
Charge is quantized, the smallest it can be is 1.6*10^-19.
Electrons have negative elementary charge and protons have positive elementary charge.
Charge quantizations means no charges in the middle.
Electrostatic Induction
Electrostatic induction is the ability for charges in one object to affect charges in another object.
Charged objects can be charged through friction or a conductor/insulator.
Induction is next to conduction is touching.
Electrons move, not protons.
Insulators have fixed electrons, conductors have free electrons.
Calculating Electric Force
Two charges next to each other is just Electric Force.
Resistivity
Resistivity property of a material that describes how it resists charge.
Structure of an object determines resistivity, can be changed by temperature.
Superconductor metals have very low resistivity.
Always look at temperature when looking at resistivity tables.
Resistors
You need an EMF for a circuit to work.
Potential different in electricity is voltage, how much electrons are flowing is current.
Resistors resist the flow of current.
Capacitors build up potential energy in a circuit.
Resistance can be increased through material and geometry, long resistor, low cross-sectional area.
Resistor related to resistivity (material, direct), length (direct), cross-sectional (indirect).
Resistivity property of a material that describes how it resists charge.
Structure of an object determines resistivity, can be changed by temperature.
Superconductor metals have very low resistivity.
Always look at temperature when looking at resistivity tables.
Resistors
You need an EMF for a circuit to work.
Potential different in electricity is voltage, how much electrons are flowing is current.
Resistors resist the flow of current.
Capacitors build up potential energy in a circuit.
Resistance can be increased through material and geometry, long resistor, low cross-sectional area.
Resistor related to resistivity (material, direct), length (direct), cross-sectional (indirect).
Electric Circuits
Voltage and current make up a circuit
EMF, Resistors, Capacitors, and Switches are parts of a circuit
A switch has to be closed for a circuit or that part of the circuit to run.
Ohm's Law, V=IR
Series - one element after another, parallel - multiple elements.
Voltage is always the same in parallel circuits.
Voltage and current make up a circuit
EMF, Resistors, Capacitors, and Switches are parts of a circuit
A switch has to be closed for a circuit or that part of the circuit to run.
Ohm's Law, V=IR
Series - one element after another, parallel - multiple elements.
Voltage is always the same in parallel circuits.
Kirchhoff's Junction Rule
Current we have coming into a junction has to equal the current coming out.
Also known as the conservation of charge.
Current we have coming into a junction has to equal the current coming out.
Also known as the conservation of charge.
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