Unit 2 Test
Energy in Forms
Energy- ability to cause change
Kinetic Energy- Energy of an object that is due to motion
Potential Energy- Energy that an object has due to its position, condition, or chemical composition
Greater Mass- Greater Kinetic Energy
Mechanical Energy- sum of an objects kinetic energy and potential energy
Kinetic Energy
Sound energy- energy caused by vibration of particles in a medium such as steel, water, or air
Electromagnetic Energy- energy transmitted through space in a form of electromagnetic waves
Electrical Energy- results from position or motion of charged particles
Chemical Energy- form of potential energy; amount of chemical energy in a molecule depends on the kinds of atoms and their arrangement; sources of chemical energy are your food you eat
Thermal Energy- object is the kinetic energy of its particles; Higher temp, particles move faster
Nuclear Energy- source of nuclear energy is nucleus of atom
Energy Transformation- takes place when energy changes from one form to another form
Law of Conservation of Energy- energy cannot be created nor destroyed but con only change forms
Mass increases, Kinetic Energy increases
Heat is always transferred from a higher temp to a lower temp
Kinetic Theory of Matter- all particles that make up matter are constantly in motion
Solid- not free to move around;vibrate back and forth in same position and are held tightly together
Liquid- Move more freely than solid but not as much as gas; constantly sliding around
Gas- lost of space to move around; collide with one another
Temperature- measure of the average kinetic energy of all the particles in an object
Kelvin Scale- commonly used by physicists; Freezes= 273 K Boils= 373 K
Fahrenheit Scale- Commonly used in U.S.; Freezes= 32 F; Boils= 212 F
Thermometer- temperature is measured by this
Degrees- equally spaced units between two points
Absolute Zero- motion of particles stop
Celsius Scale- commonly used around the world; Water Freeze=0 C; Boils=100 C
Thermal Energy- total kinetic energy of all particles in a substance
Water with higher temp= more thermal energy
Average Kinetic energy decreases, than temp decreases
Heat is measured 2 ways; Calorie; amount of energy needed to raise the temp of 1 gram of water by 1 degree Celsius and Joules
Heat- Energy transfers from an object with a higher temp to an object with a lower temp
Conduction- transfer of energy as heat from one substance to another trough direct contact
Insulator- material that is a poor conductor of heat
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Convection- transfer of energy as heat by the movement of a liquid or a gas
Radiation- transfer of energy by electromagnetic waves
Renewable Resource- energy source that can be easily reproduced or replaced by nature
Heat always flows from hot to cold
Nonrenewable Source- energy source that can not be produced, grown, or restored as fast as it is used
Sun is earths main energy source
Fossil Fuels- energy resources made from carbon-rich plant and animal remains
Coal- formed from remains of dead plants; nonrenewable
Natural Gas- gases that become trapped in rock formations, half of U.S. uses natural gas to heat home; produces carbon dioxide
Petroleum- "rock oil"; mined on land or in ocean; separated into fossil fuels such as gasoline, diesel, and jet fuel
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Solar energy- renewable; converted into electrical energy
Nuclear Energy- nonrenewable; harmful radioactive wastes
Hydroelectric Energy- renewable; powered by water cycle; can only be produced by large amounts of water
Wind Energy- renewable; depends on steady strong wind
Geothermal Energy- extracted from heat stored within the Earth; Renewable
Energy from burning Biomass- renewable; recently dead organic material that can be used as fuel; burning them releases carbon dioxide