matter something that occupies space and can be perceived by one or more senses; a physical body, a...
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MATTER
Something that occupies space and can be perceived by one or more senses; a physical body, a physical substance, or the universe as a whole
Matter
Atoms
• Matter is made up of atoms
• Atoms consist of protons, neutrons and electrons
• The electrons orbit around the atomic nucleus, where the protons and electrons are located
Mass• A measure of the
quantity of material that an object contains
• Independent of the object’s location
• Same on Earth or Moon• Mass = Gram,
Kilogram • This element is Carbon
(C) because it has 6 electrons (blue) and 6 protons (red)
Gravity and Gravitational Force
• An attractive force between two bodies which have mass
• The greater a bodies’ mass, the greater the gravitational force it will exert on another body
• Weight = Newton (acceleration of mass by gravity)
Gravity
• Gravitational Force holds the Solar System together
• Sun is by far the largest object in the Solar System, therefore it exerts the greatest gravitational force, and is the center of the Solar System
Energy
• Property of an object or system that allows it to do work
• Any object in motion has energy. If a string were tied around the object, it could pull another object
• All objects above 0 degrees K have energy
Potential Energy• Energy that is available for work if it is started by activation energy
• Gasoline has potential energy, it only needs a spark to start it
• Car on a hill has potential energy. Taking off the brake would be the activation energy
• Spark plug is activation energy for a car’s gasoline
Kinetic Energy
• Energy of Motion• Any object in motion
has kinetic energy• One jeep is using its
kinetic energy to tow
the other jeep (do work)
Show: All sizes - Large - Medium - Small
Heat (Radiant) Energy• Heat Energy is able to do
work when heat is transferred from a warmer to a colder object
• Heat energy only flows in one direction, from warmer to cooler object.
• Ice water always melts at room temperature, it never forms by itself
Electromagnetic Radiation
• Includes radio waves, microwaves, infrared, light and x-rays
• EM radiation is always a form of radiant energy
Heat (Radiant) Energy
• If heat energy flowed from a colder to a warmer object, then we would have a snowball Earth, as the Earth got colder and the Sun got hotter
Heat (Radiant) Energy
• Heat always flows from the Sun towards Earth, not from the Earth to the Sun, because the Sun is hotter than the Earth
Chemical Energy
• Energy released by a chemical reaction
• Usually released as heat and mechanical energy (the motion of the particles in the reaction)
Gasoline, Fossil Fuels
• Most common source of chemical energy in use in the world
• Includes coal, oil and natural gas
• Requires Activation Energy (it needs to be started or “lit”) to be useful
Nuclear Energy• Energy which is
produced by nuclear fusion (fusing two hydrogen atoms together) or nuclear fission (splitting large atoms into smaller atoms)
• Sun uses fusion, first atomic bomb used fission
• Current reactors use fission (splitting atoms)
Mechanical Energy• A form of Kinetic
Energy imparted when something moves (a machine), breaks or is smashed together (a collision), or slides (friction).
• The mechanical energy is usually converted to heat energy
Law of Conservation of Energy
• Energy can neither be created nor destroyed; it may be transformed from one form into another, but the total amount of energy in the universe remains constant. Kinetic energy is translated into mechanical energy in this collision.
Law of Conservation of Energy
• When we take a header off of our bike and scrape our skin, kinetic energy is turned into mechanical (friction) and heat energy. We “skin” our legs.
Law of Conservation of Energy
• In auto accidents, kinetic energy is turned into mechanical and heat energy when the cars collide.
Law of Conservation of Energy
• When a bomb goes off, chemical energy is turned into heat and mechanical energy (the mechanical energy is what is broken by the bomb)
Formation of the Solar System
Big Bang
• Universe was born from a point in space. How? Who knows.
• In the beginning it was pure energy.
• As it expanded and cooled, atoms “condensed”out of the “energy” soup
• These atoms condensed into stars and galaxies.
Early Stars and Supernovas
• The earliest stars were Blue Giants. They burned their nuclear material very fast, then collapsed from gravity, spewing heavy elements into space
Solar Nebula
Planet Formation
• Little “Space Rocks” collided and stuck together
• As they got bigger, their gravitational force attracted more rocks (bigger bodies exert more gravitational force)
Planet Formation
• Each collision released heat as kinetic energy was changed into heat energy (Law of Conservation of energy)
• When Planets finally formed, they had hot interiors
Earth is Formed
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