Energy
Mechanical energy is the sum of the potential and kinetic energy.
UNITS: a = [m/sec2], F = [kg•m/sec2] (newton), work = pe= ke = [kg•m2/sec2] (joule)
1ev is an energy unit equal to 1.6 x 10-19 joules
Gravitational potential energy increases as height increases.
Kinetic energy changes only if velocity changes.
Mechanical energy (pe + ke) does not change for a free falling mass or a swinging pendulum. (when ignoring air friction)
Units for Power is [joules/sec] or the rate of change of energy.
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