Chapter 9 - energy and energy resources Flashcards
the ability to do work
energy
work like energy is expressed in …
Joules
the energy of an object that is due to the objects motion
kinetic energy
kinetic energy
mv2/2 or mass x velocity2/2
the energy that an object has because of the position, shape, or condition of the object. (remember, an object accelerates as it falls due to gravity, so the higher an object is lifted above the ground the greater the potential energy.)
Potential energy
when you lift an object, you do work on it . You transfer energy to the object
gravitational potential energy
gravitational potential energy
weight x height
the amount of work an object can do because of the object’s kinetic and potential energies
mechanical energy
mechanical energy
potential energy + kinetic energy
the kinetic energy due to random motion of the particles that make up an object
Thermal energy
….is a measure of thermal energy
Temperature
energy of a compound as atoms are rearranged
chemical energy
the energy of moving electrons
electrical energy
the energy caused by an object’s vibration
sound energy
energy produced by the vibrations of electrically charged particles
light energy
energy that comes from changes in the nucleus of an atom
Nuclear energy
when nuclei join together
fusion
when a nucleus splits
fission
a change from one form of energy to another
energy conversion
storing potential energy in a material that stretches and can return to its original shape
elastic potential energy
examples of elastic potential energy are
bow and arrow, crossbow, toy airplane, and pulling a rubber band
plants use light energy to make new substances that have chemical energy
Photosynthesis
a force that opposes motion between two surfaces that are touching
friction
not all ____ is converted into ____; much is lost due to friction
potential energy, kinetic energy
a group of objects that transfer energy only to each other
Closed system
states that energy cannot be created or destroyed but can be changed from one form to another
Law of conservation of energy
Any time one form of energy is converted into another form,
some of the original energy always gets converted into thermal energy
a resource that forms at a rate that is much slower than the rate at which it is consumed (fossil fuels, nuclear energy)
Non-renewable resources
a nonrenewable energy resource formed from the remains of organisms that lived long ago
Fossil Fuels
coal, natural gas and petroleum(used to make gasoline, kerosene, wax, and plastics) are an example of what?
Fossil fuels
like a fossil fuel plants, a nuclear power plant generates thermal energy that boils water to make steam
Nuclear energy
____ is generated from radioactive elements, such as uranium
Nuclear energy
nuclear fission is used
Nuclear energy
a natural resource that can be replaced at the same rate at which the resource is consumed
Renewable resources
sunlight is changed into electrical energy through solar cells
Solar energy
falling water from a dam turns a turbine which is connected to an electric generator
Hydroelectric energy
the kinetic energy of the wind turns the blades of a windmill which turns an electric generator
Wind energy
thermal energy caused by the heating of Earth’s crust, the steam is used to turn turbines which turns an electric generator
Geothermal energy
organic matter such as plants, wood and waste that can be burned to release thermal energy
Biomass
(page 262.)
_______ of food is converted into _______ when you are active.
Chemical energy, kinetic energy
