Download PT-Ch8 Using Energy and Heat

1. Using Energy and
Heat (Ch8)
2. Forms of Energy
(8.1)
3. Energy
energy
5. Ability to cause change
5. Energy is used in everyday life
3. Potential Energy
Potential Energy (PE)
5. Stored energy due to the interaction between objects or
particles
5. Objects that fall due to gravity
5. Movement between particles due to magnetic/electrical
forces
4. Gravitational Potential Energy
Gravitational PE
5. Everything above the ground has gravitational PE
5. Depend on 2 factors: mass (grams) and distance
(meters)
4. Chemical Energy
Chemical Energy
5. Energy stored in and released between bonds of atoms
4.
Nuclear Energy
Ex: Sun
Ex: Power Plant
Electricity
Nuclear Energy
5. Energy stored in and released from the nucleus of an
atom
5. Nuclear fusion (nuclei come TOGETHER)
5. Nuclear fission (nuclei break APART)
3. Kinetic Energy
KE
5. Energy due to motion
4. KE of Objects
5. Relate to mass (grams) and speed=distance/time (m/s)
5. Objects of larger mass and equal speed (will have
greater KE)
Electric Energy
Ex: Light/muscle movement
4. Electric Energy
5. Energy in an electric current
5. Movement of electrons (e-)
3. Combined KE and PE
A system is a collection of
parts that are interact and
act together as a whole
4. Mechanical Energy
Mechanical Energy
5. KE+PE= mechanical energy (the sum in a given
system)
5. Energy that can cause another object to move
4. Thermal Energy
Thermal Energy
Proportional/direct
relationship
5. Sum of KE and PE of the particles that make up an
object
5. When PE , KE , or both ; thermal energy also 
3.
wave
Energy Carried By Waves
5. Disturbance that transfers energy from one place to
another without transferring matter
5. In the example of a raindrop hitting the water, the wave
caused, only allows energy to move outward (not
matter)
4. Sound Energy
Sound energy
5. Energy carried by sound waves (move through matter)
5. Sound travels through matter by vibrating particles.
5. Raindrops causes sound through particles in the air
4. Radiant Energy
Radiant Energy
Ex: Light energy
5. Energy carried by electromagnetic waves
5. Does not need to travel through particles
(matter/vacuum)
5. Electric and magnetic waves move ┴ (perpendicular) to
each other
Wavelength
Ex: Radio waves, infrared
rays, visible light, UV rays,
X-rays and Gamma rays
Cause sunburn
5. Is the distance from one point on a wave to the nearest
point just like it.
5. Wave length (shorter) ; Frequency Energy 
Wave length (longer) ; Frequency Energy 
5. Gamma Rays and X-rays are often used in medical
procedures
5. Ultraviolet (UV rays) rays have wavelengths that are a
bit shorter than light
5. Infrared is felt as heat and is used to change channels
(via remote control)
5. Radar, television, and radio waves have long
wavelengths compared to visible light
2. Energy Transfers and
Transformations (8.2)
3. Law of Conservation of Energy
Law of Conservation of
Energy
Ex: Flashlight
5. Energy cannot be created or destroyed, only
transformed
5. Chemical (battery)electricalradiant (light) & heat
4.
Energy transfer
Energy Transfer
5. Energy moves from one object to another without
changing form
4. Energy Transformations
Energy Transformations
5. When form of energy is converted to another form of
energy
4. Energy and Work
work
W=F x D
5. Transfer of energy that occurs when a force makes an
object move in the direction of the force.
5. Work can be done when a force is acting on an object
5. Work is equal to the Force multiplied by the Distance
5. Unit for Work = J (joules); Force = N (Newtons);
Distance = m (meters)
4. Inefficiency of Energy Transformations
Ex: Chemical energy in a
flashlight does not fully
change to light energy since
some converts to thermal
(heat)
5. Some energy may appear to be lost. This is due to
transfer not being only part of one thing.
Do not always get what you
put in
4. Open Systems
Open System
In a vacuum/space
Closed System
5. System that exchanges matter or energy with the
environment
4. Closed Systems
5. System that does not exchange matter or energy with
the environment
3. Energy Transformations and Electrical Energy