Quantum Mechanics 1 Guaranteed A+

Quantum Mechanics 1 Guaranteed A+ Review of Properties of a Free Particle (3) 1. Energy is not quantized! 2. They cannot have definite energy! 3. It is always described by a wave packet! 4. wave packet always spreads with time! (just like in classical physics) wave packet a group of superposed waves that together form a traveling localized disturbance, especially one described by Schrödinger's equation and regarded as representing a particle annihilation operator 'lowing operator'; something operator 'raising operator'; "the wave packet always spreads with time"--why? you have a superposition of different momenta, different momenta move with different speeds, and this gives a distortion of the wave packet as it moves with time variance, standard deviation related to expectation value (mean) ...and standard deviation is the square root of the variance momentum operator kinetic energy, momentum, and potential energy operator SE-time evolution and SE-time-independent; TISE SE time dependent, TDSE wave number, k the phase delay per unit length; lamda=2pi/k potential energy Potential energy is mechanical or stored energy from an object that comes from factors such as its position relative to others, internal stress, electric charge or its condition rather than motion. This object has the capability of producing energy as these conditions change - this energy could be kinetic energy, chemical energy, radiant energy, thermal energy or sound energy.