Physics - Chap 7: Gravitation

Kepler's First Law

States that the planets move in elliptical paths, with the Sun always at one focus.

Kepler's Second Law

States that an imaginary line from the Sun to a planet sweeps out equal areas in equal time intervals.

Kepler's Third Law

States that the square of the ratio of the periods of any two planets is equal to the cube of the ratio of their average distances from the Sun.

Gravitational Force

The attractive force between two objects that is directly proportional to the mass of the objects.

Law of Universal Gravitation

States that gravitational force between any two objects is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.

Gravitational Field

The field that surrounds any object with mass; equals the universal gravitational constant, times the mass of the object, divided by the square of the distance from the object's center.

Inertial Mass

A measure of an object's resistance to any type of force.

Gravitational Mass

The size of the gravitational force between two objects.

Kepler's Third Law (Formula)

(Ta/Tb)^2 = (Ra/Rb)^3

Law of Universal Gravitation (Formula)

F = G (m1 m2) / r^2

Period of a Planet Orbiting the Sun (Formula)

T = 2π * sqrt(r^3 / GM)

Speed of a Satellite Orbiting Earth (Formula)

V = sqrt(GM / r)

Period of a Satellite Orbiting Earth (Formula)

T = 2π * sqrt(r^3 / GM)

Gravitational Field (Formula)

g = GM / r^2

Inertial Mass (Formula)

m = Fnet / a

Gravitational Mass (Formula)

m = (r^2 * F) / GM