Module 5 : MODERN PHYSICS
Lecture 26 : Wave Nature of Particle - the de Broglie Hypothesis
 
$\displaystyle \Delta p_y = \frac{h}{\Delta y} = \frac{6.63\times 10^{-34}}{10^{-4}}= 6.63\times 10^{-30}\ {\rm kg\ m/s}$
The angular spread of the beam is given by
 
$\displaystyle \tan\theta = \frac{\Delta p_y}{p_x} = 0.1$
  so that the spread $ \theta = 5^\circ 47'$.
  Similar uncertainty relationship exists for other pairs of observables. For instance, if we wish to measure the energy $ E$ of a particle with an accuracy $ \Delta E$. According to uncertainty principle, we may determine the time at which the particle has such an energy only with an uncertainty $ \Delta t$ where
$\displaystyle \Delta E\Delta t \approx h$

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