energy and its forms describe the relationship between work and energy. relate kinetic energy to...
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Energy and Its Forms
Describe the relationship between work and energy.
Relate kinetic energy to mass and speed. Analyze how potential energy is related
to an object’s position and give examples of gravitational and elastic
potential energy. Give examples of the major forms of
energy and explain how each is produced.
In an avalanche, a mass of loose snow, soil, or rock suddenly gives way and slides down the side of a mountain.The avalanche releases a great amount of energy.
Energy and Work
Work is done when a force moves an object through a distance.
Energy is the ability to do work.
Energy is transferred by a force moving an object through a distance.
Work is a transfer of energy.
Energy has different forms. A. The sun gives off energy in the form of
heat and light. B. Plants convert sunlight into food. C. People convert food energy into muscle
movement.
Energy and Work
EnergyMany forms of energy can be
classified into two general types:
Kinetic EnergyPotential Energy
Kinetic Energy
The energy of motion is called kinetic energy.
The kinetic energy of any moving object depends
upon its mass and speed.
Potential EnergyPotential energy is energy that is stored as
a result of position or shape.
Two forms of potential energy are:
Gravitational potential energy
Elastic potential energy
Gravitational Potential Energy
Potential energy that depends upon an object’s height is called gravitational
potential energy.
An object’s gravitational potential energy depends on its mass, its
height, and the acceleration due to gravity.
This type of potential energy increases when an object is raised to a higher
level.
This diver has gravitational potential energy as she stands at the end of a diving
board. She gained the
potential energy by doing work—by
climbing up the steps to the diving board.
Potential Energy
Place two items at different heights…WHICH DO YOU THINK HAS MORE
POTENTIAL ENERGY? WHY?Gravitational PE depends on an objects height. GPE increases when an object is
raised to a higher level.GPE depends on the mass of something, its height, and the acceleration due to gravity
(g).
Gravitational Potential Energy
When this musician pulls the string of her cello to one side, the
string is stretched and gains
potential energy.
Potential Energy
Elastic Potential Energy
The potential energy of an object that is stretched or compressed is known as elastic potential energy.
EX: springs, guitar strings, bike shocks
The musician adds energy to the cello string by plucking it.
The energy stored in the stretched string is potential energy.
The stored energy is converted into kinetic energy when the string is
released and it vibrates.
Elastic Potential Energy
All energy can be considered to be one of three forms:
Kinetic energy, Potential energy, andenergy in fields such as those produced
by electromagnetic waves.
Each of these forms of energy can be converted into other forms of
energy.
Forms of Energy
Forms OF ENERGYMechanical
Electromagnetic Electrical Chemical ThermalNuclear
What is Mechanical Energy?
Energy due to a object’s motion (kinetic) or position (potential).
The bowling ball has mechanical energy.
When the ball strikes the pins, mechanical
energy is transferred to the pins!
Examples of Mechanical Energy
Mechanical Energy
Not limited to machines.
Mechanical energy is the sum of an object’s PE and
KE.
What is Thermal Energy? Thermal energy = Heat energy
The heat energy of an object determines how active its atoms are.
A hot object is one whose atoms and molecules are excited and show rapid
movement.
A cooler object's molecules and atoms will show less movement.
What is Chemical Energy? Energy that is available for
release from chemical reactions.
The chemical bonds in a
matchstick store energy that is
transformed into thermal energy when the match
is struck.
Examples of Chemical Energy
When bonds are broken, the
released energy can do
work. All chemical
compounds, including fuels such as coal and gasoline, store energy.
This family is using the chemical energy of burning wood to produce thermal energy for heating marshmallows.
Forms of Energy
What is Electrical Energy?
Energy associated with electric charges.
Easily transported
through power lines and
converted into other forms of
energy
What is ElectromagneticEnergy?
Light energy or energy that travels through space
in the form of waves.
Includes energy from gamma rays, xrays,
ultraviolet rays, visible light, infrared rays,
microwave and radio bands
Lightning bolts transfer electric charge.
Galaxies are giant structures in space
that typically contain billions of stars. The
stars give off enormous amounts of
electromagnetic energy.
Forms of Energy
The nucleus of an atom is held together by strong and weak nuclear forces, which can store an enormous
amount of potential energy. The energy stored in atomic nuclei is
known as nuclear energy. Nuclear fission releases energy by splitting
nuclei apart. Nuclear fusion releases energy when less massive nuclei combine to form a more
massive nucleus.
Nuclear Energy
QUIZ TIME!What type of energy
cooks food in a microwave oven?
ELECTROMAGNETIC ENERGY
What type of energy is the spinning plate
inside of a microwave oven?
MECHANICAL ENERGY
QUIZ TIME!What energy
transformation occurs when an electric lamp is
turned on?
ELECTRICAL ENERGY
ELECTROMAGNETIC ENERGY
QUIZ TIME!Electrical energy is
transported to your house through power lines.
When you plug an electric fan to a power outlet,
electrical energy is transform into what type
of energy?
MECHANICAL ENERGY
What types of energy are shown below?
Mechanical and Thermal Energy(Don’t forget friction)
What types of energy are shown below?
Electrical, Mechanical andElectromagnetic Energy
What type of energy is shown below?
Chemical Energy
What type of energy is shown below?
Thermal Energy
Draw a diagram showing the flow of energy transformations in a car from starting the vehicle to driving. You
should have 5 different types of energy.
Energy Transfer
Chemical
Electrical
Electr
ical
Electrical
Sound(mechanical)
Light(Electromagnetic)
ThermalMechanical
Tomorrow… How do you know
what you know?
Energy of motion.
Kinetic energy of a moving object depends upon its mass and its speed.
K.E. = m x v2
2
Kinetic EnergyKinetic Energy
Energy due to position or stored energy.
Gravitational Potential Energy (G.P.E)
G.P.E = Wt. x Ht.
Potential EnergyPotential Energy
Energy is never created or destroyed.
Energy can be converted
from one form to another but
the total energy remains
constant.
Law of Conservation of Energy
Law of Conservation of Energy