Energy and Work
Thermal
A measure of the total kinetic energy in a substance's atoms.
LEDS
Convert almost all electrical energy to light.
Energy Efficiency
Measure of usable energy after a conversion.
Open Systems
Most systems are ___ _____ and exchange energy with the space that surround them.
Energy
The ability to do work or the ability to cause change.
Nuclear
The nucleus of an atom is the source of ______ energy.
Thermal
Also caused by friction (two objects rubbing against each other)
Law of Conservation of Energy
Energy cannot be created or destroyed, although it may be transferred or transformed.
Unwanted
Energy conversions may produce _______ forms of energy.
Mechanical
Energy due to an objects ability to move.
Desired; Undesired
Energy may be split between the _________ (usually some form of work) and __________ energy (heat or friction).
Electrical
Energy produced by electrons moving through a substance.
Sound
Energy produced when an object is made to vibrate.
Chemical
Energy stored in the chemical composition of matter.
Open System
Ex. Earth.
LEDS
Ex. Hybrid cars increase the fuel efficiency in cars.
Mechanical
Ex. Moving your textbook from your backpack to your desk.
Chemical
Ex. Striking a match, combining vinegar, and baking soda to form CO2 gas, breaking light sticks releases ________ energy.
Electromagnetic
Ex. light, gamma rays, x-rays, UV, infrared, radio, and microwaves.
Sound
Ex. voices, whistles, horns, and musical instruments can produce _______ energy.
Elastic Potential Energy
F= -kx (F=N; x=m; k=N/m)
Electromagnetic
Form of energy that can be reflected or emitted from objects through electrical or magnetic waves traveling through space.
Gravitational Potential Energy
GPE=mgh (GPE=J; M=kg; g=9.8 m/s^2; h=m)
Displacement
In order for a force to qualify as having done work, there must be a ____ and the force must have caused the _______.
Kinetic Energy
KE=1/2mv^2 (KE=J; M=kg; V=m/s)
Kinetic Energy
Speed has a greater effect on the amount of ________ than mass.
Elastic Potential Energy
Springs are a special instance of a device that can store _________ _________ _________- by compressing and stretching.
Energy Conversions
Technology can improve the efficiency of ______ ________.
Elastic Potential Energy
The amount of ______ _______ _______ stored is related to the amount of stretch of the object; the more stretch the more energy.
Gravitational Potential Energy
The energy due to an objects position above the earth's surface.
Closed System
The energy flow out of a system is small enough to be ignored.
Chemical Potential Energy
The energy store in a substance, such as sugars or fats, due to its chemical composition.
Elastic Potential Energy
The energy stored in elastic materials, such as rubber bands and springs, as the result of their stretching or compressing.
Kinetic Energy
The faster an object moves, the more ________ it has.
Kinetic Energy
The greater mass of the moving object has the more ______ it has.
Thermal
The internal motion of atoms is called _____ because moving particles produce heat.
Mass; Gravitational Potential Energy
The more _______ and object has the greater ________ ________ ___________
Height; Gravitational Potential Energy
The more __________ that an object is elevated, the greater the _______ ________ ________.
Kinetic and Potential
The most common energy conversion is between ________ and ___________.
Mechanical
The sum total of kinetic and potential energy.
Gravitational Potential Energy; Height
There is a also a direct relation between ____ _______ ________ and the ____ of an object.
Gravitational Potential Energy; Mass
There is a direct relation between _________ __________ __________ and the ______ of an object.
Work
This is what happens when a force acts on an object to cause displacement of the object.
Hooke's Law
This law states that the force needed to extend or compress a spring by some distance is proportional to that distance.
Work
W= Fd (w=J; F=N; d=m)
Energy and Matter
What makes up the universe?
Hooke's Law
When the load does not exceed the elastic limit, the material is said to obey Hooke's Law.
Nuclear
When the nucleus splits (fission), _______ energy is released in the form of heat and light energy.
Thermal
_____ energy causes changes in temperature and phase of any for of matter.
Electrical
_____ energy lights our homes, run motors, and makes out TVs and IPod work.
Kinetic Energy
_____ is determined by an object or organism's mass and speed.
Matter; Energy
_____ is substance, and _______is the mover of the substance.
Nuclear
______ energy is also released when nuclei collide at high speeds and join (fusion).
Sound
______ energy travels out as waves in all directions.
Kinetic Energy
______ is the energy of motion.
Sound
______ needs a medium to travel through, such as air, water, wood, and even metal.
Nuclear
_______ energy is the most concentrated form of energy.
Potential Energy
_______ is energy that is stored in an object as a result of its position, shape, or chemical composition.
