acceleration due to gravity
the acceleration due to gravity at the earth’s surface – g = 9.8m/s2 or 32 ft/s2
cenrtipetal acceleration
acceleration, directed toward the center of a circular path, that produces uniform circular motion
centripetal force
center-pointing force
conservation of momentum
the physical law that states that total momentum before an interaction is equal to the total momentum after the interaction
copernican system
a heliocentric system advocated by Copernicus with planets in circular orbits around the sun
dynamics
the branch of physics concerned with the causes of motion and how the nature of the object affects the motion
force
a push or a pull
geocentric system
the system of the planets and sun in orbit around the earth
gravitational field
a region of space in which a measurable gravitational force is indicated by the force exerted on a test mass
gravitational force
an attractive force due to the presence of another mass
gravitational mass
the mass of an object as determined by measuring the object’s weight within a given gravitational force field;
heliocentric system
the system of planets in circular orbits around the sun
impulse
the product of the force on an object and the time of contact
inrtial mass
the mass of an object as determined by exerting a force on an object and measuring its acceleration;
inverse square law
the fact that gravitational forces vary inversely as the square of the distance of separation
Keplers law of planetary motion
(I) Planets orbit the sun in elliptical orbits with the sun at one focus. (II) A line from planet to sun sweeps out equal areas in equal times. (III) The cube of the orbital radius and the square of its period of revolution are factors in a ratio that is constant for all members of an orbiting system.
momentum
The product of the mass of an object and its velocity.
newtons law of motion
(I) Every object continues in its state of rest or of uniform motion in a straight line, unless it is compelled to change that state by forces acting on it. (II) The acceleration of an object is directly proportional to the net force acting on the object and inversely proportional to the mass of the object. (III) Every action force is accompanied by an equal and opposite reaction force.
ptolemaic system
a geocentric system advocated by Ptolemy, with the earth at the center and moon, sun, and planets orbiting in circular orbits
weight
the force of gravitational attraction of the earth or any other body on an object
