Energy and Energy Resources
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Transcript Energy and Energy Resources
What is energy?
Energy- the ability to do work
The unit for energy is Joule (J)– just like work.
mv2
KE
2
Kinetic Energy- energy in motion
All moving objects have kinetic energy
Kinetic Energy = KE = mv2
2
What is the kinetic energy of a car that has a mass of
1,200 Kg and is moving at a speed of 20 m/s?
KE= 1,200 x 20 x 20 ÷ 2 = _____________
What is the kinetic energy of a car that has a mass of
2,400 kg and is moving at 20 m/s? How does this kinetic
energy of the car in the above example compare?
KE= 2,400 x 20 x 20 ÷ 2 = _____________
Potential Energy- The energy that an object has because
of the position, shape, or condition of the object
Gravitational Potential Energy - energy stored as a
result of position or height.
▪ GPE = weight x height
What is the gravitational potential energy of a book
with a weight of 13 N at a height of 1.5 m off the
ground?
GPE= 13 x 1.5 = _________________
What is the gravitational potential energy of a cat that
weighs 40 N standing on a table that is 0.8 m above the
ground?
GPE = 40 x 0.8 = ___________________
What is the gravitational potential energy of
a diver that weights 500 N standing on a
platform that is 10 m above the ground?
GPE = 500 x 10 = _____________________
Mechanical Energy- the total energy of
motion and position of an object.
Mechanical Energy (ME) = potential energy + kinetic energy
(J)
(J)
(J)
What is the mechanical energy of a book being held in
the air that has 100 J or potential energy and 50 J of
kinetic energy?
100 + 50 = __________________
What is the mechanical energy of a goose standing on a
rock that has 75 J of potential energy and 60 J of kinetic
energy?
75 + 60 = _______________
Thermal Energy- is all of the kinetic energy
due to motion of the particles
Chemical Energy-The energy in a compound
that changes as its atoms are rearranged
Electrical Energy- is the energy of moving
electrons.
Sound Energy- is caused by an object’s
vibrations.
Light Energy- Produced by the vibrations of
electrically charged particles.
Nuclear Energy- The energy that comes
from the nucleus of an atom
Friction-A force that opposes motion
between two surfaces that are touching
Energy cannot be created or destroyed.
Energy changes forms.