Fields Flashcards
Definition of Gravitational fields
It is a space where a small test mass experiences a force due to another mass.
Definition of Electrostatic fields
It is a space where a small positive charge experiences a force per unit charge
Definition of electric potential
The capacity for doing work by a change in position of the positive test charge. Also known as voltage
Definition of gravitational potential
The gravitational attraction a point P is equal to work done per unit mass required to take a test mass from infinity to point P
2 properties of gravitational potential
Always negative and when it is infinite it is equal to zero
2 components of equipotential surfaces
Points with the same gravitational potential can be joined together to form an equipotential surface.
Field lines are perpendicular to equipotential surfaces.
Explain density of field lines
It is positively correlated to the field strength.
What does E(p) stand for?
Potential energy, for gravitational and electrical
What does g stand for?
Field strength
What does V(g) stand for?
Gravitational potential
What does V(e) stand for?
Electric Potential
What does E stand for?
Electrical Field strength
What does G stand for?
Gravitational Constant
What does k stand for?
Coulomb constant
What does M stand for?
Mass
What does Q stand for?
Charge
What does r stand for?
Separation distance
What does m stand for?
Mass
What does q stand for?
Charge
What does F(g) stand for?
Gravitational Force
What does F(e) stand for?
Electric Force
What does V(esc) stand for?
Escape Velocity
What does V(orbit) stand for?
Velocity of orbit
What does W stand for?
Work done
What does ΔV stand for?
Change in gravitational potential between two points
What does Δr stand for?
Distance between those two points
Definition of potential gradient
Slope of a graph which plots the gravitational potential against the distance from the mass
Both equations for potential gradient
PG = - ΔV/Δr = GM/r^2
Definition of Potential Difference
The work done by moving a positive test charge from one point to another in an electric field. Also called voltage, V.
Both equations for potential difference
V = W/Q = E/Q
What is Kepler’s third law
The square of a planets period is poroportional to the cube of its mean distance from the sun.
T^2 is proportional to R^3
Equation for T^2
T^2 = 4 * π^2 / GM R^3
What does K stand for?
Kinetic energy
Equation for kinetic Energy
Potential divided by 2 and non negative
Equation of total energy
Kinetic energy + gravitational potential energy
Definition of Photons
Smallest discrete amount of electromagnetic radiation (light).
Properties of waves
Exhibit wave properties under refraction or interface and under its emission or absorption.
What does E stand for?
Photon’s energy
