Ch 4 Sect 2

1
Ch 4 Sect 2

• Energy Transfers and Transformations

2
Movement of Energy

• Energy naturally moves from areas of high energy
  to areas of low energy
• Ex-heat radiating off of a stove
• Transferring energy
• Energy stays in same form but moves to another
  object
• Transforming energy-
• Energy changes forms as it moves

3
Energy Transfers

• Electrical outlet can transfer electricity
• Example-Vandegraff machine
• Outlet Machine Human
• Heat energy can be transferred
• Example-boiling water
• Stove Pot Water

4
Energy Transformations

• Energy is like money in that it can be used in
  different forms
• Electrical energy can be transformed to
• Light energy, Heat energy,
• Other examples?

5
Energy Transformations

• Chemical energy is transformed by living
  organisms and machines
• Humans covert chemical energy into kinetic energy
  
• Chemical energy in the body is stored as ATP or
  Adenosine Tri-Phospate

6
Energy Transformations

• Machines also transfer chemical energy into
  kinetic energy
• Chemical energy used by machines is usually gas
  or diesel
• Suck, Squeeze, Bang, Blow
• 4 steps that an internal combustion engine uses
• Any engine in any gas powered vehicle

7
NRG Conversion in an Engine

• Sucks the air/gas in (intake)
• Squeezes the air (compression)
• Bang (gas ignites, causes explosion)
• Gasoline engines have a spark plug
• Diesel is explosive enough that it needs no spark
• Blows air out (exhaust)
• How Car Engines Work

8
Mass, Atoms and Energy

• Mass in motion has energy
• Mass is made up of smaller parts called atoms
• Atoms can be joined or broken apart to produce
  energy

9
Nuclear Fusion

• Joining of 2 atoms to make 1 atom
• Bonds of both atoms are broken and reformed to
  make one atom
• When bonds are broken energy is released
• Mass of the atom increases
• Nuclear Fusion Basics

10
Nuclear Fission

• Taking one atom and breaking it down to two or
  more atoms
• Energy is released when the chemical bonds are
  broken
• Mass of the atoms decrease
• Nuclear Fission Basics

11
Mechanical Energy

• Mechanical energy is the sum of total potential
  energy and total kinetic energy
• Mechanical Energy Pot Energy KE
• Energy converts back and forth from PE to KE but
  mechanical energy always stays the same
• Ex. PE70 and KE30 ME100
• PE40 and KE60 ME100

12
Law of Conservation of Energy

• Conservation of energy states that energy can
  neither be created or destroyed, therefore amount
  of energy always stays the same