Energy

  Energy:    

1. Work       W= F|| * d         Positive and negative work      Scalars     Total work         Work of  position dependent force          WA,B      work done  on the body A  by  the force B    

2. Kinetic energy         Work energy theorem - change of the kinetic energy of a body  is equal to the total work done on it          Work is also  energy in transfer       ( WA )total   is positive  then body A is gains  kinetic energy    ( WA )total  is negative  then body A loses kinetic energy           Elastic collisions

3. What is a conservative force            Potential energy for conservative force   ( Uf -Ui ) = - W conservative force            Conservation of the mechanical energy       Emech = Ki +Ui = Kf +Uf     or      (Kf-Ki ) + (Uf-Ui) = 0         Gravitational potential energy         GPE = m*g*h        Energy skate park        Work of a non-conservative force          Non conservation of the  mechanical energy         Kf +Uf  =Ki +Ui + Wnon conservative          Isolated systems and conservation of the  total energy

4. Mechanical power    P = F * v      Engine has one input power and two types of  output power ( useful and waste )     Efficiency      ( eff ) * Pinput = Puseful 

5. **Potential energy as mutual energy       W1,2  +    W2,1    =  -   {Change of the mutual potential energy}

 Forms of energy: 

• 1. Gravitational potential energy

  2. Electromagnetic energy

     • • Electrostatic, Chemical

       • Magnetic

       • Light

  3. Nuclear energy

     • • Fission - heavy nuclei

       • Fusion - light nuclei

  4. Macroscopic kinetic energy

     • • Fluid/gas in motion (wind)

       • Solid in motion(asteroid)

  5. Microscopic kinetic energy

     • • Thermal kinetic energy and temperature

       • Thermal potential energy and heat capacity

  6. Matter antimatter energy

  7. Who knows what

     • • Energy of empty space

       • Vacuum energy

       • Dark energy

• Total potential energy as mutual property(coordinate free scalar considerations) in position space    Individual potential energy exist only for non interacting particles immersed in global  force field     Immunity to translation, rotations and boost but NOT time translations    Link between potential energy and force

• Total kinetic energy as a individual  property in velocity space    Immunity to spacial translations and rotations but NOT time translations    Link between kinetic energy and force

• Work as transferred energy either Kinetic to potential or Potential to kinetic

• YES the total energy is immune to TIME translation    In every time interval total kinetic energy gained/lost is equal to the total potential energy lost/gained