6.2 - Particles - Electric fields Flashcards
What is electric field
A region which charged particles are subject to an electrostatic force
What shape do point charges have
Radial fields (circle)
How can you model charged sphere
As a point charge at the centre of the sphere
What do field lines show
The path a positive charge would take when placed in an electric field
Which direction do the field lines point
Positive to negative
How does distance affect strength of electrostatic force
The greater the distance the weaker the force
What is the equation for Electric Field Strength
E = F / Q
What is Coulomb’s law
The force between any 2 point charges is proportional to the product of their charges
What is the equation for force between 2 point charges
F = Q1Q2 / 4πεor^2
What is permittivity
The ability of a material to transmit an electric field
What is the formula for electric field strength
E = Q / 4πεor^2
What is permittivity of freespace (εo) (constant)
8.85x10^-12
What is the formula for work done when moving a charge in an electric field
Work done = Force x distance
What is the formula for the potential at a point in an electric field
V = W / Q
What is the formula for the capacitance of a parallel plate capacitor
C = Aεoεr / d
εo = permittivity of free space
εr = relative permittivity of electric
