PCM. Changes in Matter Benchmark 4

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PCM. Changes in Matter Benchmark 4
Describe energy transformations involved in
physical, chemical and nuclear changes, and
contrast their relative magnitudes.
2
Energy Types
As we have seen, there are three types of
energy Kinetic Potential Radiant
Kinetic Energy is the energy of MOTION. Potential
Energy is STORED energy. Radiant Energy is energy
associated with waves from the electromagnetic
spectrum (heat, radiation, light, etc.).
Energy is neither created nor destroyed,
only converted between these forms
3
Roller coaster energy transformation
Interactive Coaster Animation
Energy conversion Tutorial
EnergyHow many forms?
An introduction to energy
4
Kinetic Energy

• Kinetic Energy is the energy of motion. Any
  object in motion has Kinetic Energy.
• The amount of Kinetic Energy depends on two
  factors
• The mass of the object.
• 2. The speed of the object.

Which has more Kinetic Energy? A bowling ball
rolling down the hallway at 1 m/s or a bowling
ball rolling down the hallway at 5 m/s? A bowling
ball rolling down the hallway at 1 m/s or a golf
ball rolling down the hallway at 1 m/s?
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Potential Energy
Potential Energy is stored energy. Energy can be
stored in various forms. 1. Energy can be stored
by raising an object above the ground
(gravitational potential energy). 2. Energy can
be stored by compressing or stretching a spring
(elastic potential energy). 3. Energy can be
stored in the chemical bonds of a compound
(chemical potential energy). 4. Energy can be
stored in the form of electricity (electrical
potential energy). Energy can be released from
each of these forms into Kinetic Energy!
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Radiant Energy
Radiant Energy is energy associated with waves
from the electromagnetic spectrum (heat,
radiation, light, etc.). There are various
forms. 1. Heat from any source (the sun, fire,
etc.) is infrared waves. 2. Visible Light Energy
can be stored by compressing or stretching a
spring (elastic potential energy). 3. Gamma Rays
and X-Rays are high energy electromagnetic waves.
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Real-world contexts
Common physical, chemical and nuclear changes,
including changes of state, burning, electrical
decomposition of water, photosynthesis, cellular
respiration, fireworks and dynamite, nuclear
power, stars.