# Lab Objectives Learn about conservation of energy with a skater dude! Build tra

Lab Objectives:
Learn about conservation of energy with a skater dude! Build tracks, ramps and jumps for the skater.
view the kinetic energy, potential energy and thermal energy (due to friction) as the scatter moves.
Experience the differences in kinetic potential and thermal energies at different planets or even at space.
Introduction:
The law of conservation of energy states that the total amount of energy in an isolated system remains constant. As a consequence of this law, we can say that energy neither created nor destroyed, but can change its form.
The total energy E of a system (the sum of its mechanical energy and its internal energies, including thermal energy) can change only by amounts of energy that are transferred to or from the system. If work W is done on the system, then
W = DE = DEmech + DEth + DEint
If the system is isolated (W = 0), this gives
DEmech + DEth + DEint = 0
The skate park is an excellent example of the conservation of energy. For the isolated skate-track-Earth system, the law of conservation of energy equation has the form
DEmech + DEth = 0
Mechanical Energy: The mechanical energy Emech of a system is the sum of its kinetic energy K and its potential energy U:  Emech = K + U
The conservation of mechanical energy can be written as
DEmech = DK + DU = 0. It can also rewritten as  K1 + U1 = K2 + U2
In which the subscript refer to different instants during an energy transfer process.
Gravitational Potential Energy: The potential energy associated with a system consisting of Earth and a nearby particle is gravitational potential energy. If the particle moves from y1 to height y2 , the change in gravitational potential energy of the particle-Earth system is
DU = mg(y2 – y1)=mgDy
Kinetic Energy: The kinetic energy is associated with the state of motion of an object. If an object changes its speed from v1 to v2 , the change in kinetic energy is
DK = K2 – K1 = ½ mv22 – ½ mv12
Simulation: Open Energy Skate Park