Transcript Mechanical Energy

Mechanical Energy
Mr. Bombick
7th Grade Science
Types of Energy?
Mechanical Energy Definition
The form of energy due to the relative
position of interacting bodies
(potential energy) or to their motion
(kinetic energy). Mechanical energy
may be in the form of either potential
energy or kinetic energy or both.
Potential Energy (PE)
The most common type of potential energy
associated with mechanical energy is gravitational
potential energy. Gravitational potential energy can
be defined as follows:
Gravitational Potential Energy = weight (Newtons) X height (meters)
Other Types of
Potential Energy?
Potential Energy (cont.)
Potential energy, gravitational or otherwise,
has significance only when it changes—
when it does work or transforms to energy of
some other type.
Kinetic Energy (KE)
Energy of motion is called kinetic energy
(KE). The kinetic energy of an object depends
on mass and speed.
Kinetic Energy = 1/2mass X speed2
KE = 1/2m X v2
Work-Energy Theorem
The work-energy theorem states that work
equals the change in kinetic energy. The work
refers to the net work done in the system.
Work =
KE
Conservation of Energy
Energy cannot be created or destroyed; it may
be transformed from one form into another, but
the total amount of energy never changes.
Conservation of Energy
RDX or PETN Example
Conversion of the potential energy of the explosive
into other forms of energy.
What are some of the other forms
of energy released after the
explosion?
Internal Combustion
Engine Example
Conversion of the potential energy of
gasoline into other forms of energy
What are the other forms of
energy produced?