Apologia Physical Science Module 11
Universal Law of Gravitation
1. All objects with mass are attracted to one another by gravitational force. 2. The gravitational force between two masses is directly proportional to the mass of each object. 3. The gravitational force between two masses is inversely proportional to the square of the distance between those two objects.
Four Fundamental Forces of Creation (weakest to strongest)
1. Gravitational Force 2. Weak Force (weak nuclear interaction) 3. Electromagnetic Force (also called Lorentz force) 4. Strong Force (strong nuclear interaction)
Solar Wind
A "wind" resulting from particles being pushed away from the sun
Comet
A ball composed of dirt, dust grains, and "ice," that rotate around the sun in an elliptical orbit
Ceres
A dwarf planet that exists inside the asteroid belt
Eris
A dwarf planet that is larger than pluto
Gravitational Force
A force that attracts all objects that have mass
Weak Force
A force that governs radioactive processes in atoms
Strong Force
A force that is responsible for holing together the center (nucleus) of an atom
Electroweak Force
A force which the electromagnetic force and the weak force are both facets of
Pluto
A former official planet, which is now recognized as a dwarf planet
Oort Cloud
A hypothesis suggesting a large shell of icy bodies explaining where certain (long-period) comets came from
Graviton
A hypothetical tiny particle that two massive objects exchange
Tail (of a comet)
A long, glowing line of gases from the coma
Meteorite
A piece of a meteor that has fallen to the ground
Dwarf Planet
A small unofficial planet that orbits around the sun
Kuiper Belt
A smaller band of comet material existing just beyond Neptune and the source of short-period comets
General Theory of Relativity
A theory that is a broad explanation of an entire way of looking at physics and what causes gravitational force; According to the GTofR, gravity is not a force but a result of how mass bends space and time.
Perturbation
A variation in the motion of an object in space
Geocentric View of the Solar System
A view of the solar system that places the earth at the center of the solar system
Heliocentric View of the Solar System
A view of the solar system that places the sun at the center of the solar system
Meteor
An asteroid that has entered earth's atmosphere, burning up in white-hot flames due to friction
Meteoroid
An asteroid that has intersected earth's orbit, but nothing more
Electromagnetic Force
An attractive or repulsive force against objects with electrical charge
Universal Law of Gravitation Formula
An equation developed by Newton that allows physicists to calculate the strength of gravitational force between two objects
Satellite
An object that orbits around a planet
Solar System
An orderly arrangement of planets and their moons
Short-Period Comets
Comets that take less than 200 years to make an orbit; the Kuiper belt is considered a source for these comets.
Long-Period Comets
Comets that take more than 200 years to make an orbit; originates from the Oort Cloud
Very Long-Period Comets
Comets that take more than 5,000 years to make an orbit
Planetary Rings
Small bodies of rock, ice, and frozen gases encircling a planet in the form of a ring
Nucleus (Atom)
The center of an atom, containing protons and neutrons
Centripetal Force
The force necessary to make an object move in a circle. It is directed perpendicular to the velocity of the object, which makes it point to the center of the circle
The Galilean Satellites
The four biggest of Jupiter's satellites discovered by Galileo (Io, Europa, Castillo, and Ganymede)
Inner Planets
The four planets of our solar system closer to the sun than the asteroid belt (Mercury, Venus, Earth, and Mars)
Outer Planets
The four planets of our solar system farther from the sun than the asteroid belt (Jupiter, Saturn, Uranus, and Neptune)
Coma
The fuzzy atmosphere around the comet
Asteroid Belt
The region of our solar system containing the highest concentration of asteroids
Centripetal Acceleration
The resulting acceleration from centripetal force
Nucleus (Comet)
The solid part of a comet
Period (of a comet)
The time it takes for a comet to orbit the sun
Sublimate
To change from solid to gas (skipping the liquid state)
