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Day 1: Types of Energy Storage. Energy. What is Energy?. Def : Ability to cause change in a system Unit joules Symbol E. Electrical Energy. Chemical Energy. Nuclear Energy. Radiant Energy. UV. Energy can be transformed from one form to another. Mechanical Energy.
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Day 1: Types of Energy Storage Energy
What is Energy? Def: Ability to cause change in a system • Unit joules • Symbol E
Electrical Energy Chemical Energy Nuclear Energy Radiant Energy UV Energy can be transformed from one form to another. Mechanical Energy
Energy Storage • Energy is energy • There are no different kinds • There are simply different ways of storing energy within a system For Example: • You can store information in a book, on a computer hard drive or CD • No matter how it is stored it is the same information
Energy Storage The Total Energy (ET) of a “closed” system is equal to the sum of its mechanical and internal energies • The 2 Major Types are Mechanical & Internal • ET = Emec + Eint Can change motion Energy of the particles
Mechanical Energy Em Def: Can cause a change in motion
Kinetic Energy (KE) Ek • Def:The energy stored with the actual motion of the object • depends on mass and velocity
Potential Energy (PE) • Def:energy due to the position of the system relative to another object • usually involves a ‘field’ (i.e. - gravity, magnets, etc.)
Gravitation Potential Energy (GPE) • Def:energy due to an object’s position (height) above the ground • Depends on mass and distance (height)
Elastic Potential Energy (ELPE) • Def:energy due to a system being stretched or compressed
Electromagnetic Potential Energy • Def:energy due to position in an electric or magnetic field
Internal Energy Chemical Energy Energy is not stored in the bond • Atoms store the energy due to their position relative to each other
Have you "lost" energy? • Internal energy that the system does not use again is called Dissipated Energy • Symbol: DE or ED • Usually from friction or when the object is deformed
Word Bank KE GPE ELPE E & M DE What Kind of Energy??? GPE E&M A curling iron heating on the edge of the counter. A magnet holding family pictures of the refrigerator. GPE E&M ELPE A sling shot just in launch position. KE DE Hockey puck slowing down on an ice rink. KE GPE A rock falling off a steep cliff. KE GPE DE A child sliding down a playground slide.
Bar Graphs & Energy Transformations
System vs. Surroundings • System (it): only the factors we are paying attention to • Surroundings: everything else You MUST define your system
Energy Bar Graphs • Bar Graphs are used to represent how energy is stored in a system • Your set up will look like this: Initial Bar Graph Final Bar Graph GPE KE ELPE DE System Definition GPE KE ELPE DE
Bar Graph Practice • A ball is held at rest 1m above the ground and it is then released and has fallen halfway to the ground Initial Bar Graph Final Bar Graph GPE KE ELPE DESystem Definition GPE KE ELPE DE
Law of Conservation of Energy Newton’s Cradle The total energy of a“closed system” remains constant. • “Closed system” meansno energy enters or leaves the system
Open system, the real world, KE causes friction, skater eventually comes to a stop
The total energy did not change. • Some of the energy got shifted from mechanical energy to internal energy. • KE Thermal Energy
What Kind of Energy??? GPE E&M A curling iron heating on the edge of the counter. A magnet holding family pictures of the refrigerator. GPE E&M ELPE A sling shot just in launch position. KE DE Hockey puck slowing down on an ice rink. KE GPE A rock falling off a steep cliff. KE GPE DE A child sliding down a playground slide.
What types of energy are shown below? Mechanical and Dissipated Energy (friction)
What type of energy is shown below? Chemical Energy
What types of energy are shown below? Electrical, Mechanical and Electromagnetic Energy
What type of energy is shown below? Chemical Energy (yummy)
What type of energy storage is shown below? Thermal Energy
Draw a flow map showing the flow of energy transformations in a car from starting vehicle to driving. You should have 5 different types of energy.
Energy Transfer Sound (mechanical) Electrical Thermal Mechanical Electrical Chemical Electrical Light (Electromagnetic)
Calculations Energy
Kinetic Energy • KE = ½ mv2 • Changing velocity affects KE more than changing mass
Kinetic Energy Practice Problem How much kinetic energy does a 75kg car as it travels at 25m/s?
Gravitational Potential Energy • GPE = mgh • Mass x gravity x height above the earth
Potential Energy Practice Problem A 25Kg statue is dangling from a crane 20m above the ground. How much potential energy does the statue have? How much kinetic energy would it have if it fell?
What is the potential energy of the rock? A 59,900 J B 64,600 J C 93,100 J D 121,600 J