Electrostatics

What is a force qualitavely

A push or a pull exerted on a body

What is F as a vector defined as

Newtons second law as a rate of change of momentum

What are the 4 fundamental forces

Gravity, strong nuclear force, weak nuclear force, electromagnetism

What does electromagnetism study 

Forces between charge particles, through resultant electric and magnetic fields

What does the incorporation of relativity and quantum show and what theory is this

Particle wave duality, Einstiens theory of special relativity

What do faradays demonstrate

Electromagnetic induction

What is electron charge

-1.9×10^-19

What is the relationship of charged particles exerting forces on each other

Inverse square law

What does the inverse square law quantify

Magnitude of electrostatic force from a point charge

What is relative permittivity

A dimensionless quantity that is a measure of how easy or difficult it is for an electric field to influence a materials internal electrical structure 

What creates an electric field

Charged particles

What feels and electric field

All other charged particles in the field

What is value of electric field in metal and why

0, electrons very quickly

What is a dielectric

A material that can be polarixed

How do magnetic fields have material interactions

Through magnetization

When does electric potential energy increase

If particle moves in the direction opposite to the force on it

When can work done be expressed in terms of charge in potential energy 

If force is conserved

What is work done independent of in an electric field

Path taken from point A to point B

What does faradays law mean when work is done in an electrical field

Electrostatic forces and conservative forces

What does potential at a given point represent 

Potential energy a positive unit charge would have if it were placed at that point in the field 

What 4 kinds of source can flux be sourced from

Electrical current, fluids, light sources, electric fields

How can flux be described from Gauss’ law

Flux out of closed surface= source strength contained within a volume

If rate is doubled, what happens to flux density

Doubles

If area of flow is halved what happens to flux and flux density

Flux stays the same, flux density doubles

In a dielectric, what does applying an electric field from fixed charges result in

Movement of charge distribution due to polarization

What is Gauss’ law

Amount of displacement field flux passing through a closed surface is equal to amount of charge inside the closed surface

Where does electric displacement occur and what does it result in

Occurs in dielectric and results in a modified law due to polarization

What does the relationship between flux and charge apply to

Any shape of surface, charge anywhere within it, any distribution, charge does not mean just how much flux enters/ leaves 

How is Gauss’ law limited

Integrability of the equation

What is capacitance

Build up of charge in space leads to a buildup of potential energy

What can high voltages lead to in a non ideal system

Risk of electric break down due to the electric field

When is voltage constant across the material

In a conductor

What is the capacity of a body

Amount of charge it can sustain for a given voltage

What is a capacitor

A component with a high capacitance between two conductors

What does high capacitance show

Amount of charge stored is very high, maximises electrical energy that is stored

What 3 factors can be altered for highest capacitance

Large surface area on plates, large relative permeability in the dielectric, small distance between the plates of the capacitors

What does a ‘good’ capacitor have

High energy density, assuming the volume of plates are negligible

What should a capacitor with high energy density have 

High dielectric breakdown strength and relative permeability 

3 practical benefits for constructing a working capacitor

Increased relative permittivity, increased dielectric strength, mechanically keep the conducting plates apart 

What is increased dielectric strength good for 

Determining maximum breakdown voltage