Forces on Charges & Masses The electric field strength equation can be rearranged for the force F on a charge Q in an electric field E: Where: F = electrostatic force on the charge (N) Q = char...
Forces & Inverse-Square Law Behaviour The gravitational force between two bodies outside a uniform field (for example, between the Earth and the Sun) is defined by Newton’s Law of Gravitation w...
Orbital Motion, Speed & Energy Since most planets and satellites have a near circular orbit, the gravitational force FG between the sun or another planet provides the centripetal force needed t...
Escape Speed To escape a gravitational field, a mass must travel at the escape velocity This is dependent on the mass and radius of the object creating the gravitational field, such as a planet, a ...
Potential in a Charged Sphere The electric potential in the field due to a point charge is defined as:Where: V = the electric potential (V) Q = the point charge producing the potential (C) ε0 = per...
Potential Gradient Electric Potential Gradient An electric field can be defined in terms of the variation of electric potential at different points in the field: The electric field at a particular ...
Potential Energy Calculations Electric Potential Energy of Two Point Charges The electric potential energy Ep at point in an electric field is defined as: The work done in bringing a charge from in...
Potential & Potential Energy Work Done on a Mass When a mass is moved against the force of gravity, work is done The work done in moving a mass m is given by: Where: ∆W = change in work done (J...
Equipotential Surfaces Equipotential lines (when working in 2D) and surfaces (when working in 3D) join together points that have the same gravitational potential These are always: Perpendicular to ...
